START LAB DAILY Filmed & Processed by the Library Photographic Service University of California Berkeley 94720 | year Ratio joy in Reduction wh ll22 I = Ig lls oad). of dAA33aa — il — ay oN ww — — — | TR LT SL, ——— gag TTT Tet ttmt rtmerttet . MAIN LIBRARY UNWVERS(TY 1s CALIFORNIA Bertaley 1 Position Filming Unit no. 493 Lens no. THE MASTER NEGATIVE,FROM WHICH THIS REPRODUCTION WAS MADE, IS STORED UNDER THE SUPERVISION OF THE LIBRARY PHOTOGRAPHIC SERVICE, ROOM 20, MAIN LIBRARY, UNIVERSITY OF CALIFORNIA, BERKELEY, CALIFORNIA 9 4 7 2 0 FOR ADDITIONAL REPRODUCTION REQUEST MASTER NEGATIVE NUMBER ET —_—e————" aS AUTHOR: Ransome, James stafford TITLE: - -. How to select wood -wWor King machin- | evry PLACE : London PATE: 1333 VOLUME caLL TS 350 MASTER NO. RH NEG. NO. AUTHOR: Ransome, James Stafford TITLE. ..- How to select wood -working machinery PLACE: London DATE: ITT MICROFILMED 1982 UNIVERSITY OF CALIFORNIA PHOTODUPLICATION SERVICE HOW TO SELECT WOOD-WORKING MACHINERY. « TIMBER TRADE HAND BOOKS, No. 3. HOW TO SELECT WOOD-WORKING MACHINERY. o BY J. STAFFORD RANSOME, ASSOC. MEMBER OF THE INSTITUTION OF CIVIL ENGINEERS. LONDON: WILLIAM RIDER AND SON, TIMBER TRADES JOURNAL OFFICE, 14 BARTHOLOMEW CLOSE, E.C. /888 PREFACE. te QP pnt THE great variety of machines now in use for the conversion of wood, and the rapid improvements which have characterised their construction of late years are the considerations which suggested the compilation of this short treatise. It is obvious that in a work of the limited dimen- sions of this volume it would be impossible to go into detailed descriptions of all the wood-working machines that are made, nor is it attempted. Its object is to point out to intending purchasers the most suitable machines for their purpose, and the qualities to be looked for in such machines; while at the same time showing them the most practical manner of making their inquiries, and putting them in the way of getting at reliable and detailed particulars of their machines before com- pleting their purchase. A certain number of books relating to wood- working machinery have been published both in England and America, though not of very recent date, but, owing to their great bulk (necessitated by the vastness of the subject when any attempt is made to treat it in detail), it was a difficult, or at all events, a tedious operation to wade through them to find information on a given point. 330273 vi Preface. Wood-working machines are unfortunately often. ordered in a haphazard manner ; not only by the ordinary purchaser who buys for himself without looking about him sufficiently, but also by firms and companies who indent for certain machines to be sent to them, stipulating that they shall be constructed in exact accordance with a detailed specification made out only too frequently by some- one who has no special knowledge of wood-working machines. Constructors of wood-working machinery are constantly receiving indents of so unpractical a nature that to follow out the specification in all its details would result in the production of very imperfect, if not absolutely worthless machines. Specifications for Government requirements are notably among the above. It is by no means rare for specifications to be based on descriptions taken from some very old catalogue, the machines in which are probably obsolete at the present day. In this book there will, of course, be found some matter which is not #ew to the experienced saw-mill owner or manager, and to others who have a special knowledge of wood-working machinery. But, as above stated, many people who have occasion to use such machines know little or nothing about them until they have got them at work, and then they can only judge from the results as to whether, or not, their purchase has been successful. If such people find that by the use of their new Preface. vii machines they are losing money, or not increasing their profits, they are pretty certain to come to one of the following conclusions ; either, that they have not got the best machines for their purpose ; or, that they kave got the best machines, but that ro machinery, however perfect, can fulfil their require- ments satisfactorily. But it does not necessarily follow that either of the above surmises is correct; for there are a hundred and one causes why machinery which in reality is all that could be desired, may fail or seem to fail, among which are the following :— 1. Inefficient workmen. . Injudicious placing. . Imperfect foundations. . Insufficient horse-power. . A badly governing motor. . Prejudice against its use on the part of the foreman or men. Any one of the above faults means a serious loss to the proprietor of the machines, and I do not think that it is an exaggeration to say that most of the wood-working factories in England suffer more or less from one or another of them. During the time that the following chapters were being run through the columns of the Zimber Trades Journal, in the form of articles, I received a great number of communications from persons in different parts of the world with suggestions, catalogues, etc., some of which have been of service to me, and I would take this opportunity of thanking such people for the trouble they have taken. J.S. R. CONTENTS. ‘PREFACE . The Points of Good ad Bad Madiinery . Some Common Mistakes ... . When Inquiring for Machines “ '. The Value of Catalogues, and other Information . Prices, Estimates, Payments . Foreign Machinery ... . Second-hand Machinery ... . Motive Power—General Remarks . Motive Power—Steam .. Motive Power—Water XV. XVI XVII. XVIIL . Motive Power—Gas . Functions of Wood-working Machinery ... . Tree Felling... . Handling Logs after Felling Handling and Cross-cutting Logs in the Yard . Reciprocating Saw Frames Circular Saw Machines Band Saw Machines x1x. Fret Saw Machines xX. Cross-cut Saw Machines XXI. Saw Blades ... Contents. PAGE . Appliances for Suarping and Betting Saw Blades ... - 154 . Appliances for Adjusing wl Festing Hear Timber ... sae 161 . Planing and Moulding Machines. (Operating on XXV, XXVI. XXVII. XXVIII, XXIX. XXX. XXXI. XXXII. XXXIII, XXXIV, XXXV. XXXVI, four sides) WH es vor ron 169 Miscellaneous Planing and Moulding Machines... 180 Irregular Moulding Machines one ee .. 188 Appliances for Sharpenirg Cutters vor .. 193 Boring and Mortising Machines ... _~ we 197 Tenoning Machines ne er ert wn 204 Combined Machines ive vee ie «es 200 Lathes won see a $5 Sn ve 214 Dovetailing Machines ... oH oo .. 218 Sand-papering Machines ... - ve. 222 The Automatic Collection of Wood Refuse 226 Shafting, Bearing, and Couplings wv ve 231 Pulleys, Belting and Lubricators 7. wr 240 © XN ONS Ww NomZ NN ND Ey vw 2 ow hoa SOS n> LIST OF ILLUSTRATIONS. . Root’s Patent Boiler . Allen’s Turbine Driving Saw-mill at a Distance . Russian Design for Tree-felling Machine vor . Patent Steam Tree-feller Fee . Steam Skidding and Loading Machine . Hauling Apparatus for Logs . Circular Cross-cut Saw for Logs . Log Frame, with overhead Crank-shaft . Portable Log Frame . Breaking-down and Re-sawing Frame... . Improved Fraser Equilibrium Deal Frame . Rack-bench for Squaring Timber . American Double Rack-bench ... . Saw-bench with Hand Rack-feed . Saw-bench with Deal Sawing Apparatus . American Re-sawing Machine ... . Self-centring Saw-bench . Large Band-saw Machine for Logs . Mouw’s Patent Metal Guide Boxes ... . Band-saw for Straight or Curved Work . Fret Machine with Unstrained Saw . Fret Machine with Strained Saw List of Illustrations. . Pendulum Cross-cut Saw . Cross-cut Saw with Traversing Blade ... . Automatic Plank Cross-cut Saw . American Lumber Trimmer . Various Forms of Saw Teeth ... . . Ordinary type of Saw-sharpening Machine . Setting Apparatus for Circular Blades... . Martinier’s Sharpening Machine for Band-saws . Log Canting Machine . The ¢ Steam Nigger” ... oe ee . Travelling Table with Setting-up Dog: . The ‘“Lane-Brown ” Dog vor ove . Four-sided Planing and Moulding Machine ... . Four-sided Planing Machine, with fixed Knives . Trying-up Machine Io . Panel-planing Machine ... ore . . Combined Hand and Power Feed Planing Machine... . ¢¢ Elephant” Moulding and Recessing Machine . Mortising Machine for Joiners’ Work . Tenoning Machine for Joiners’ Work ... . The ‘“ Complete Joiner” . Armstrong’s Dovetailing Machine . The Patent *“ Cyclone ” Dust Collector . Richards’ Adjustable Ball and Socket Bearings . Clamp Coupling ... . Cross-stay for Pulleys with wrought iron Rims . Grooved Pulleys for Rope "Driving HOW TO SELECT WOOD-WORKING MACHINERY. CHAPTER L Tue Points oF Goop AND BAD MACHINERY. AN injudicious or hasty selection of wood-working machinery often results in very disastrous conse- quences to the purchaser, and it is for this reason of the utmost importance that, before investing in any plant, he should look around him thoroughly, and satisfy himself perfectly, that what he is pur- chasing is what will really best fulfil his purpose. That the best wood-working machinery is the cheapest in the long run is decidedly a fact, but that a great many people do not realise this is equally certain ; however, it stands to reason that, at the present day, when competition between mills working for the trade is so excessively sharp, the margin for profit being consequently reduced to the lowest possible figure, the firm which possesses the 14 How to Select Wood-working Machinery. most perfect machines will be in a better condition for making what profit there is to be made than its neighbours, It is true that in localities where there is no com- petition, and the saw-mill proprietor jogs along, making a tolerably profitable thing out of his busi- ness, while using antiquated or inferior tools, there is not so much occasion for him to improve his plant. But at the same time he would do well to look into matters, and find out how much money he is letting slip away annually in unnecessary labour and trade expenses for want of adequate machinery, which would otherwise have remained in his pocket, as further profit. It is the exception rather than the rule, however, to find such favoured localities as the above-men- tioned, and every year they will get rarer and rarer with the increase of competition. The best machinery, if kept at work and properly managed, will often pay its first cost over and over again in the course of a few years, and naturally it will in much less time pay for the difference between its own price and that of inferior machinery, with- out taking into consideration the expenses for repairs which bad plant inevitably occasions. Well-made machinery will last many years, and work well until it is obsolete ; and, besides this, it has the advantage of always being saleable in the event of the owner wishing to part with it. The following qualities may be taken as essential to a good machine :— I. It must do perfect work at the maximum speed. The Points of Good and: Bad. Machinery. 15 2. The best materials must be, used, -artd the. inost careful workmanship must be expended on it. 3. Its design should be as simple as possible, SO that the operator may have it easily under his con- trol. : 4. It should possess all the most recent 1mprove- ments. : 5. It should not be liable to get out of repair. 6. Its working parts should be light, and its bear- ings long, in order to attain the necessary speeds. If a machine combines all the above points it will be readily understood that it is impossible for the price to be very low, and consequently it is as well, when possible, to see a machine before buying it rather than to pin one’s faith on the statements of travellers or on catalogue descriptions. : Good machinery, however, is not the only element of success in a saw-mill, as it is equally important, as already mentioned, that a perfectly organised system for carrying on the work should be effected in the shop. The difficulties in making a choice of wood-work- ing machines are greatly enhanced by the fact that the prices of the different constructors vary enor- mously ; so much so, that it is difficult at first sight, to understand how any business at all could be done by the firms whose prices seem exorbitant by the i f others. gi oe it is no unusual thing to find a difference of 23, 50, or even Ioo per cent. between the prices of two makers for a machine described in their respective catalogues under the same title. This discrepancy 16 ‘How to Select Woosd-working Machinery. can. be partially accounted for by explaining that the different makers often construct their machines for fulfilling one purpose on very different lines, and be- stow a greater or less amount of care in design and workmanship, or use different qualities and quantities of materials in their construction. But these details are not sufficient to account for the greater inequali- ties of price, which are really due, not, as some peo- ple think, to the best makers demanding exorbitant profits—for in these times, when competition is at its keenest, they could not get them if they did demand them—but to the fact that wood-working machines for widely different purposes are often described under zdentical names. As an illustration of this I may mention that tools known as mortising machines can be obtained at any price, from about £7 up to £250; and machines described as ‘Joiners’ vary in price from £20 up to about £300. It is true that no one would be likely to mistake a £7 hand-power mortising machine for light joinery work, for a £250 machine for heavy railway waggon work ; yet it would be easy to confound some of the intermediate ma- chines, where the discrepancy is not so great, and to imagine their capabilities to be equal, when they are in reality widely different. There is a prevalent notion that the heavier a machine is the better it is, and the longer it will last ; but there was never a more erroneous idea, for although it is the worst of all faults for a machine to be too light, every pound of metal in excess of what is required is a fault, and it depends on what The Points of Good and Bad Machinery. 17 part of the machine it is, as to whether itisa serious fault or not. Any superfluous metal whatever, on a working part, is a very great mistake indeed, as it increases considerably the friction, which is the very thing of all others the engineer should reduce to a minimum. Yet there are quantities of wood-working machines in existence with working parts 100 per cent. heavier than is necessary, and consequently they cannot be driven at anything approaching a proper speed with- out undue wear. Wherever it is that the superfluous weight occurs, it always increases the cost of transport of the machine, and usually also the cost of foundations, and makes the fixing more troublesome. It is true that saw benches, and certain other ma- chines, when made heavy will stand with their own weight and require no fixing, but then they must rest on a very strong floor ; whereas had they been constructed lighter, they would have been more suitable for an upper floor, and could be fixed with four ordinary coach screws in ten minutes. It is argued by some that, if a machine is very heavy, there will not be so much vibration, and this is true enough if the parts are imperfectly balanced ; but, as a matter of fact, if the machine is properly constructed, there should be no undue vibration. The cost of the different metals employed in the manufacture of wood-working tools of the better class is but a small item compared with the design- ing and constructing of them, and the trade expenses, which are naturally high with all engineering firms. , 18 How to Select Wood-working Machinery. In fact, a well-known saw-mill engineer recently told me that the fluctuations in the metal market made so little difference to his cost prices, that he had never yet had occasion to alter the prices of his machines on that account. It is, therefore, a great mistake to suppose that because a machine is immensely massive it will be any stronger, work any better, last any longer, or be worth any more money than another, with the proper amount of metal in its construction. On the other hand, if a machine is too light, it cannot last long, and will seldom do its work properly, even for a time; its working parts are liable to bend or break, and its framework to be shaken to pieces ; and it will usually be found that bad, or, at all events, very rough fitting accompanies machines that are too light in construction, as they are got up for purchasers with small means, and are consequently sold at very low prices. Of the two I would rather have a machine too heavy than too light, as with the former the work may be obtained at a slow speed, but with the latter you cannot count on getting any good work at all. Assuming the materials employed to be of good quality, it may be said that practical designing is half the battle, and careful construction the other half ; and these two essential points must be embodied in a machine to make it worth having, for, however good the design, it will be useless if badly con- structed, and vice versd. - In designing a wood-working machine, one of the principal objects, but one which often gets too little The Points of Good and Bad Machinery. 19 attention paid to it, should be to arrange for facili- tating access to the saws, cutters, tools, &c., so that they may be readily adjusted, sharpened, and exchanged, with as little loss of time as possible ; for every minute that a machine is standing still, in a busy mill, is loss of money. Therefore, in making a choice between two ma- chines, it is very important to ascertain, not only how many feet of work each will do per minute ; but how long, and how many times a day, each will have to stand idle while saws or cutters are being changed, sharpened, or adjusted. : As regards the materials used, cast iron is, of course, the principal as far as quantity is concerned, as the main framings, beds, brackets, and other heavy parts are usually made of it. The bearings should be made of gun-metal or phosphor bronze. While wrought iron, which formerly played so im- portant a part in the construction of wood-working tools, is gradually being discarded and replaced by steel for the smaller parts, owing to the necessity of combining lightness with great strength, so that now nearly all the working parts, including often feed rollers, are made of the latter material. em ACE ST CHAPTER II. SoME CoMMON MISTAKES. IT may be taken as a general rule that, to reap the full advantage from machinery of any sort, it must be kept running continually; but men often fall into the error of buying a very costly machine, which will do a great deal more work than they require, when, by a little careful looking around, they might have found something to answer their purpose equally well, for less money. Another common mistake, made by the unini- tiated, is to buy a machine of too large a capacity for their ordinary requirements, which is a distinct waste of money. As an instance of this, let us suppose that a man requires to saw a number of logs into planks, and that nearly all of them come within the limit of a 24 in. frame, whereas he occasionally has a few which run a good deal bigger, say 40 in. I should say that it would probably not pay him to put down a frame capable of dealing with 40 in. logs, for it would cost half as much again as a 24 in. frame, and would not work so fast, would take more power to drive it,and would be more expensive to keep working. But the question as to whether or not it would Some Common Mistakes. 21 be worth his while to put down a machine capable of sawing somewhat more than 24 in. in diameter could only be actually determined by surrounding circumstances, and by the proportionate numbers of the large and small logs. On the same grounds, it is usually a mistake to put down a combined machine, which is capable of doing a great variety of operations, when only a few of them are required to be performed, except at rare intervals. For a combined machine is necessarily complicated in its construction, and is, consequently, more difficult to adjust and work, and the advantage of being able to do extra operations from time to time may not be sufficient to compensate for the extra trouble and delay caused by the difficulty of getting at the working parts. A simpler machine would also have the advantage of being cheaper in first cost, and in wear and tear, and also in the power required to drive it. As a matter of fact, combined machines are losing favour very much, on account of the above-men- tioned inconveniences, and it may be taken as a general rule that it is an economy to put down separate tools for the different purposes. There are, of course, circumstances under which this rule does not hold good, and these will be dealt with later on ; besides which, it does not apply in cases where the combining of operations does not complicate the construction of the machine. It is also a great mistake to order machines fromany but a recent catalogue, as wood-working machinery is still making such strides that the chances are, c 22 How to Select Wood-working Machinery. anything thus-ordered would be obsolete, or, at all events, not so perfect as it should be, and, therefore, unless distance or other circumstances render it diffi- cult or impossible to do so, the latest editions of the catalogues should be obtained before ordering. An important point, which is often overlooked, especially in England, is the saving to be effected by the employment of special machines for special pur- poses. It often happens that a man has to turn out enormous quantities of a certain article, and that he, year after year, employs ordinary machines, chosen from some catalogue, whereas, if he took the trouble, and cared to go to the expense of having a special machine, or plant of machines, constructed for the purpose, he could materially reduce the cost of labour and the waste of material, while increasing the output and improving the quality. Some years ago I had occasion to report on the manufacturing economy of accompany which was in the habit of making for its own use 400,000 wooden packages. When I looked into the system of manu- facture, I found that the waste was very considerable, as not only was the machinery very slow, and the labour very heavy, but the unnecessary waste of wood in making these 400,000articles was sufficient to have made 70,000 more. However, although over £ 3,000 was annually being converted into saw-dust, and although the necessary machines would have paid for themselves out of the saving they would effect during the first six or eight months, no altera- tion was sanctioned until two years after my report. I am far from suggesting that people should put Some Common Mistakes. 23 down machinery whenever they are recommended to do so by a saw-mill engineer ; but I would urge them to consider what can be saved by adopting suitable plant, and discarding worthless machines, as it very often means the difference between profit and loss. CHAPTER IIL WHEN INQUIRING FOR MACHINES. AFTER the purchaser has determined in his mind what operations and what quantity of work he wishes to do by mechanical means, and, after having carefully calculated what it costs him to do it at present by hand labour, so that he can compare it with the capabilities of the machines later on, the next step is to apply for catalogues to the various makers of wood-working machines. If they are unknown to him, and he does not happen to have friends who can give him their names, the simplest way is to look through the advertising columns of some journal in which they are in the habit of advertising, such as the Zimber Trades Journal, The Engineer, or Engineering ; these being the three English journals which con- tain the most names of these firms. Catalogues and price lists should then be applied for to the various firms selected from the list, and when writing, particulars as to requirements should be stated. A great deal of trouble and corre- spondence may be obviated by couching the inquiry in a practical and concise form, so that the manu- When Inquiring for Machines. 2% facturer may obtain a knowledge of what is wanted, as it not unfrequently happens that, when he knows what there is to be done, he can bring under the purchaser’s notice some machine or machines which, by reason of their being quite new, or of a special nature, have not found their way into his general catalogue, or the printed matter which he would forward in the ordinary course, but which would do the work in question much better than the ordinary machines. I have known many cases where orders from the Colonies and abroad have been delayed many months by the purchaser omitting to state some small detail, which, had he thought for a minute, he would have known to be necessary for the execu- tion of the order, and which information he would have had no difficulty in supplying. With a view to obviating inconvenience of this sort, I think it well to point out here the various particulars which should be given when inquiring for wood-working machinery. Besides the details of the various operations to be done, the quantity of material to be got through should be stated, such as the number of feet of sawing or planing required in a given time, say a day of ten working hours. The quality of the wood to be dealt with, whether it is hard or soft; and whether it is in the log, or the plank, to start with. The extreme dimensions of the logs, deals, or planks to be cut ; and any other particulars which may touch the capacity of the machines. 26 How to Select Wood-working Machinery. If the machines to be ordered are destined to supplement a plant already existing, the position and speed of the shaft which is to drive them should be stated, so that the manufacturer can give the dimensions for the driving pulleys, and let the purchaser know whether any intermediate shafting will be necessary. The diameter of the driving shaft should also be stated, if the manufacturer is to supply the driving pulleys as well as the machines. Another important point to mention, especially when inquiring about the heavier classes of machinery, is as to whether or not from the presence of water near the surface of the ground on which the machines are to be placed, or from other causes, it is inconvenient or impossible to excavate to the extent of, say, six or eight feet below the floor level of the mill. For if this is the case, and the manufacturer knows it, he will, as likely as not, be able to submit the design of a machine which, while not requiring so much depth of foun- dation as would be the case under ordinary circum- stances, will do the work equally satisfactorily. If the purchaser has no machinery as yet, but is in possession of a building which he intends to make his saw-mill, it is, as a rule, well to give the dimensions of it, so that the manufacturing engineer may make a plan, showing the machines in the positions in which they can be worked to the best advantage. With the dimensions should be given the positions of the doors, windows, and any obstacles which may occur in the interior of the building ; it should also be stated at which points the ingress of When Inquiring for Machines. 27 the raw, and the egress of the finished, material should take place. If neither machinery nor building exists, and a plan is required, the limits of the ground at disposal for building purposes should be sketched to scale, and any waterways, roads, or railways, which may bound it, or may happen to be in the immediate neighbourhood, should be shown in, as also the difference between the ground level and water level. It must be borne in mind that, as a rule, no charge is made for the drawing up of such plans by the constructing engineers, more especially if they receive the order for the machinery eventually, and that as their experience will enable them to place the machines in the best positions as regards driving and working them, it is more satisfactory, from all points of view, that they should do so. CHAPTER 1V. THE VALUE oF CATALOGUES, AND OTHER INFORMATION. THE catalogues of the different makers vary as much as their prices, and, if many have been applied for, they will take some time to wade through. Some are well got up, with good engravings, and carefully written letterpress, containing a good deal of useful information ; but these are, unfortunately, in the minority : many will be very roughly and imperfectly executed, and some will be even un- grammatical and incoherent. The quality of the machines can often be judged in advance, a good deal, by the style of the catalogue ; and when it is remembered that the catalogue is the first thing to attract the attention of the would- be purchaser in a definite manner to a manufacturer, I cannot help wondering why some of the latter do not spend more money and care on compiling their books ; for it must not be forgotten that first impressions go for a good deal very often, and rightly too. A purchaser naturally starts with more confidence in a maker whose catalogue he can understand, and .when he sees that considerable trouble has been Value of Catalogues, and other Information. 29 taken to make the book interesting, or, at all events, readable, he instinctively comes to the logical con- clusion that such a manufacturer would naturally take the same pains in the construction of his machines ; whereas if he finds the information in the catalogue imperfect, and the engravings badly executed, so that he cannot arrive at any definite notion of the machines, he is apt to give less atten- tion to the products of such a firm, and their book is liable to find its way into the waste-paper basket. The different styles of catalogues, the varying prices of the machines of different makers, already alluded to, and the indiscriminate manner in which machines are named, all tend to confuse the pur- chaser, and it is for this reason advisable, whenever he, can, that he should see the machines before effecting his purchase. But, as this is not always possible, he will be obliged, under such circum- stances, to content himself with what guarantee he can get, and there are a variety of ways of covering oneself from much risk. Arrangements may, perhaps, be made for the machines to be fixed, and run in the works where they are constructed, and that they shall not be taken over, although ordered, until they have performed the work promised to the satisfaction of the purchaser, or his representative. Another way is to withhold the payment, or a portion of it, until the machines are at work satisfactorily on the purchaser’s premises. Some manufacturers do not object, if they have confidence in their customer, to let him have the 30 How to Select Wood-working Machinery. machines on trial for a month or two ; but, if they do this, it is probable that they are rather ick at the time, A practical way, too, of ascertaining the value of a machine is to ask the manufacturer for the names of firms to whom he has supplied similar tools, and to apply to them by letter, or, better still, to go and see their machines in operation. In any case, all the saw-mills there are within reach should be visited by the intending purchaser; but he should not assume that, although a machine appears to work well, and is spoken highly of by its users, it is by any means the best that can be obtained. It is very possible that it only appears to give good results because there does not happen to be a better one in the neighbourhood. Whereas if, instead of ordering similar machines from the same makers straight away, he takes the trouble to look a little more into the matter, he will very likely find that the existing firms in his neighbour- hood are using very antiquated tools, and that he can beat them out of the field, without difficulty with the more modern, or more perfect machines obtainable at the present time. ; Theletters from the constructors whichaccompany their catalogues will not present such a pleasing variety as the catalogues themselves; they will all be worded in much the same way, or, at all events they will all point the same moral, viz., that the machines of their respective firms are Just what are required. It is not improbable, if the purchaser is within Value of Catalogues, and other Information. 31 get-at-able distance, that he will receive the flying visit of the representative of one or more firms before he has had time to look into any of the documents before him, and when, consequently, he is not ready to receive them. Although one may not happen to have friends who are experienced in this class of machinery, there are usually plenty of people ready to come to the fore with advice on the subject of how and where to buy; and although, doubtless, there may be many whose opinions are genuine, their advice is not necessarily, on that account, any the more worth following. On the other hand, there are not a few who are influenced in their recommendations solely by what they hope to get out of the trans- action. It is, therefore, as well to rely, in the absence of experienced friends, on one’s own observations and the guarantees of the manufacturer, who will probably not object to be bound by all reasonable conditions to answer for the capability of his machines. : CHAPTER V. Prices, ESTIMATES, PAYMENTS. THE prices quoted in the different lists are nearly always subject to a certain amount of reduction, whether in the form of a cash discount or otherwise. The amount to be deducted depends very much on which maker it happens to be, and whether he happens to be busy or slack at the time. With some constructors their prices seem to be merely nominal, and can be squeezed down to an absurdly low figure ; that is to say, that any price that can be got will be taken. But, when such is the case, the transaction is not a satisfactory one, for it must mean one of two things—either the manufacturer must lose money on it, or the machine cannot be as well made as it should be. But as manufacturers do not care about working at a loss,as a rule, it may be assumed that the latter alternative is the more likely of the two. Although there is a certain amount of elasticity with all printed prices, enormous discounts are not given by reliable firms, except under unusual circumstances—for instance, when they are anxious to get their machines introduced into a locality, Prices, Estimates, Payments. 33 and they become willing to lose money for adver- tisement’s sake. Some wood-working machines require so many extras—that is to say, items not included in the printed price of the machine, such as cutters, augers, saws, internal belts, striking gear, foundation bolts, &c.—that, if ordered before these are ascertained, the purchaser may find that he will have to spend a great deal more than he anticipated originally. It is, therefore, as well to get the manufacturers to give an estimate or pro formd invoice of the machinery, including all these extra details, having settled previously exactly what you want to do, so that the actual figure which the machinery will cost is arrived at in a definite manner. If no plan of the factory has been made, the estimate cannot go beyond the internal belts of the machines, unless the speed and diameter of the driving shafts and the lengths of the driving belts are assumed; but if a plan is made, and the machines are shown in position, the constructor can estimate exactly for the driving belts and pulleys, besides the shafting, plummer blocks, &c. To avoid complications, a neff estimate is the simplest means, and each item should be priced separately, so that the difference in price would be at once apparent if any of the items were knocked out or duplicated. A separate price should be given for delivering the machines to a given locality, as also for fixing the same, and starting them at work if required. When a constructor gives a price for fixing 34 How to Select Wood-working Machinery. machinery of this class, it does not mean that he will undertake the foundation work, as it has some- times been thought, but that he will send down one or more experienced fitters to do the skilled work of fixing, whilst the purchaser supplies the un- skilled labour to assist in unloading and shifting the heavy pieces about, as may be required. Although the purchaser makes the foundations, it is the constructor’s business to supply the neces- sary drawings, to which they are made some time before the machines are delivered, and it should be understood that no charge should be made for such drawings. Arrangements can, no doubt, be made with the constructor to do the foundation work, but it is usually a mistake to do so, as he must naturally have to charge heavily for doing work of this sort in a place which is new to him ; whereas the pur- chaser, if he has not any men of his own for this class of work, at all events knows all the contractors in the neighbourhood who could carry it out on advantageous terms, at local prices. In the case of orders for shipment, or long rail- way journeys, the items cf packing and delivery, fo.b, must be taken into consideration; this usually adds from 4 to 10 per cent. to the price of the machines, according to how they are packed, &c. Of course, the cheapest way to get one's machines is to pay cash for them, but, as this is not convenient always, it may be as well to refer, in a brief manner, to the different modes of payment in vogue, although Prices, Estimates, Payments. 35 to many there will be nothing very instructive in what I am going to say. The term cask is very elastic ; it depends a good deal on the confidence the seller has in his customer. It may mean anything between money down with the order and money within a short time after the machines have been at work satisfactorily. When the term cas’ is applied to a transaction where the goods are to be shipped, it usually means part of the money with the order, and the balance when the goods are ready for shipment, or shipped; or the whole of the money against bill of lading. The best makers do not court an extended credit as a rule, though they seldom object to giving any reasonable amount when the necessary references are forthcoming; and they are pretty constantly required to take a part payment in cash, and draw for the remainder at four or six months, and per- haps renew a part for a longer period. Then, of course, the purchaser has to pay more for his machines. Buying machinery on the purchase-hire principle is frequently resorted to by purchasers without means, and is greatly encouraged by the makers of inferior machines. The payment often extends over two, or even three years, and is carried out in many different ways, one of the simplest being for the manufacturer to draw on the purchaser for the whole amount, at the shortest date the latter will allow, undertaking to renew at stated intervals for all but a portion, which is determined on beforehand, thus lessening the amount until the whole is paid off. 36 How to Select Wood-working Machinery. This necessitates a legal agreement, for which the purchaser pays, besides the expenses of renewing and interest. The manufacturer also usually screws a plate on to each machine, on which are words to the effect that the machine is his property; which plate is not removed until the last payment has been effected. This precaution is taken with a view to secure the manufacturer against a bill of sale being taken out on the machines, and to enable him to take them back in the event of the bank- ruptcy of his customer. The purchaser, naturally, often objects to this plate, and in such a case some other arrangement must be come to. From every point of view, I should say, the purchase-hire system, for this class of machinery, is better avoided, if possible, as it is unsatisfactory to both parties, except, perhaps, when the purchaser happens to fail, after having paid most of the money, and then, if the constructor succeeds in getting the machines back, and they are in good condition, he probably makes a profit, but a good firm would prefer not to have to do such a thing. 1 of English make. CHAPTER VL FOREIGN MACHINERY. AMERICA is the most serious competitor of England in the manufacture of wood-working machinery, for although her competition is not felt by the best English makers, for machines required zz England, yet in foreign countries the cheapness of her machines, and the energetic way in which they are pushed, undoubtedly lessen the number of orders received by English firms. There are quantities of American wood machines in use in England now; but it is only on account of their price, and not of their quality, and it is for this reason that the competition in England is felt only by our cheaper manufacturers. There is an idea among some people that an American machine will turn out work faster than an English one, but I have tried in vain to find one that would do so when doing work of an equal quality, and with the same amount of horse-power behind it, although I have had occasion to inspect a great many at work in various countries. To prove this, it is only necessary to buy an American machine for a given purpose, and test it against one D HE a a pes nRE Sed 38 How to Select Wood-working Machinery. It is true that in the States the operations of sawing, planing, and moulding are frequently got through in larger quantities in a given time than we are in the habit of doing them, but this is only at the expense of the quality of the work, and by employing enormous horse-power, and wasting what we should call a vast quantity of wood. English machines would do at least the same, but no one would work them under similar conditions here, as quality of work and economy of wood are two of the most essential points in European countries, where the market is fastidious and timber very expensive. It is for this reason that when you bring an American machine into Europe, where you imme- diately have to study the quality of the work to be turned out, you cannot get better results from it than from another. There is no doubt that were the enormous pro- tective duties, which are at present enforced in the States, removed—a thing not at all likely to happen —there would be a large market for our machines in that country ; for, in spite of the fact that our prices are higher than theirs, and the duty and transport add at least another 50 per cent. to their cost, some of our best makers from time to time sell machines to that country. I am bound to say that I do not think there would be many American wood-working machines sold in England if we had the same duties in vogue here, for they would be shorn of their principal attraction, viz., cheapness. Foreign Machinery. 39 The American machines which find their way over here are very light, and considerably rougher in appearance than the English, and as a rule are carelessly, put together, nor do they last so long as ours. But at the same time, there are often many little points about the details of their construction which are wanting in some of the English-made machines, and which our manufacturers would do well to adopt. As in England we make our machines to last a long time, with an object, viz., because the purchaser not only does not wish to have the bother and expense of changing them, but reckons on being able to hand them down from generation to genera- tion (which, by the way, is a bad look-out for the constructor, who is, however, forced to make them with this view, in order to sell them at all) ; so the Americans have an object in making their machines roughly, which is that when an American buys a wood-working tool, he does so with the intention of putting it on one side the next day, if he finds a better one to replace it. At least that was the explanation which I heard given at the Institution of Civil Engineers, at a recent discussion, where the question of the merits of machines constructed in the two countries was raised, and it seemed to me a very correct one. I must not leave the question of American machinery without stating that the Americans are far ahead of us in the way they organise the work in their saw-mills, and also in the various appliances they use for assisting the machines, thereby cheapen- 40 How to Select Wood-working Machinery. ing the cost of the work, by reducing the number of hands employed. They have been driven to do this by the very high wages they have to pay. But we also have to pay very stiffly for labour, especially skilled labour, and English saw-mill owners will do well to take into consideration the advantages, from an economic point of view, to be reaped by applying a better organised system in their works, and not to stop short at the extra expense of putting down some of these labour- saving appliances, which effect a continual and substantial economy in the working of a saw-mill. The English constructors are only too anxious to supply them, and, in fact, do make a great many for foreign and colonial orders, the result being that at the present day, owing to this want of enterprise on the part of our millowners, there are numbers of timber-converting establishments on the Continent, and elsewhere, equipped with better English machines and appliances than the English mills themselves. / There is a great cry out that mouldings, and other work, can be imported cheaper, ready finished, than they can be made here ; and it is nut to be wondered at when the foreigners employ the best English-made machines they can get, while many of the saw-mills here are using antiquated machines, turning out, certainly, in many cases, not more than half as much as they should. France, Germany, Austria, and Sweden, all manu- facture wood-working tools to some extent, but, although their prices are cheap, there is no market for them in this country, except for a few special tools. Foreign Machinery. For instance, the French makers have taken up the manufacture of veneer-cutting machines a good deal more than English firms, and they also, up to the present, have succeeded in making better band- saw blades for light work than any other nation, although their band-saw machines are not always sufficiently well constructed to do justice to the blades. Of the four countries above mentioned, the French machines are probably the best all round, but, on account of their inferiority to English and American machines, they hardly touch the question of ** How to Select Machinery,” as they should not be selected at all : so there is no occasion to deal further with them here. Throughout this chapter I have spoken of the best English machines, when comparing them with those of other countries, and left inferior ones out of the question, so that, in justice to the foreigner, I would add that, although the best wood-working machines are English, some of the worst ones I have seen have also been of British manufacture. CHAPTER VII. SECOND-HAND MACHINERY. THE buying of second-hand machinery is always attended with great risk, and can only be recom- mended under exceptional circumstances. As a rule, little or nothing is known about the ante- cedents of a second-hand machine, either as to how long it has been in use, or—what is more important still—how it has been treated. It is exceedingly difficult to get at its true history, as the only people who know anything about it are the people who are interested in getting rid of it. It must not be forgotten that, when a man sells a machine which he bought originally for his own work, it is usually because, for some reason or another, it is of no use to him ; and it is not alto- gether impossible that it may turn out equally - unserviceable to the new purchaser ; although there are undoubtedly cases when second-hand plant may be met with and bought to advantage. I should say that, as a rule, the bankrupt sale of a large saw-mill is the most likely place to find something worth having, but it is very difficult to know what you will get for your money until you have got it, as little opportunity is given for Second-hand Machinery. 43 inspecting the plant which is under the hammer, and the most practised judge in the world can only form an approximate estimate as to what it will cost to put an old machine in working order, unless he has an opportunity of taking it apart and thoroughly inspecting it. The auctioneer will, doubtless, give the machine a very excellent cha- racter ; but, although I should be sorry to suggest that he is anything but a conscientious man, I should be more sorry still to have to endorse any of his statements. When buying from a second-hand dealer it is as well to arrange, if possible, to take a machine on trial for a time, and return it if it does not suit. It is, however, as a rule, difficult to do this, as the dealer, not being the constructor, does not care tc give any guarantee. The dealer is not altogether wrong in refusing a guarantee—I should do the same were I in his place—for he must necessarily know but little of the machine beyond the fact that he gave so much for it, and that he is anxious to get as much more as possible. He does not see the force of being hampered by conditions which might result in his having to take the machine back, or pay for its being repaired. It is better for him to sell it even at a comparatively small profit, so long as he gets it off his hands unconditionally. There will always be a certain amount of trade in second-hand machines, for there will always be a certain number of men who are anxious to start a plant who cannot—or think they cannot—afford the cost of new machines ; besides those men who ‘44 How to Select Wood-working Machinery. reckon that they will, sooner or later, light on exactly what they want for a mere song, and that, by their great experience in machinery, they will be able to grasp the opportunity when it presents itself. I know more than one firm, doing a fair amount of business, and employing numbers of machines, who pride themselves on never buying any but second-hand tools; but I should question very much if it pays them to do so. Not only on account of the extra repairs which must necessarily ensue, but because the old types of machines are practically useless, at the present day, to firms who are working in competition with others who have new plant, to say nothing of the inconvenience and trouble of waiting and looking about for machines to fulfil their requirements, which do not always turn up when wanted. I am of opinion that, in most cases, machinery, so bought, costs more in the long run than new. Another man who buys second-hand is he who puts himself in the hands of an unscrupulous mill- wright, who recommends him to do so. The millwright, foreseeing a repairing job, which will turn out a source of profit to himself, undertakes to make the machine as good as new. The price of it is probably low, compared with a new one, but when the purchaser gets in his bill of repairs, -he finds out that, by adding the amount to what he originally paid for the machine, there is not so much difference after all between them ; perhaps it may surpass the cost of a new machine. Let us Second-hand Machinery. 45 hope, any way, that it will work as well now it is repaired. Some of the cheaper makers of saw-mill machines, whose customers lie a good deal among people of but little capital, who buy on the purchase-hire principle, go in for the second-hand trade, and cultivate it considerably; and as they are constantly getting their machines back on their hands, through their customers not completing the purchase-hire payments, this is not the least lucrative part of their business. The better firms of saw-mill engineers do not care about the second-hand trade, but it happens some- times that they come across, or hear of, some of their own machines for sale, and it is not unusual for them to guarantee them, as they often know their history, and have confidence in their own make. Under such circumstances one does not, as a rule, pay such low prices as would be paid for a chance machine, especially if the makers put them in repair, but, on the other hand, the purchaser is much safer. - : When a machine is bought from the firm who manufactured it, one may, under ordinary circum- stances, suppose that the seller is as anxious as the purchaser that it shall fulfil the latter’s requirements, .as the reputation of the former is more or less at stake. But in picking up a chance machine this is not the case, as, from the moment it is paid -for, everything is at the purchaser’s risk, the former owner caring very little, as a rule, whether it does its work or not. . 46 How to Select Wood-working Machinery. The worse the state of trade, the better is the chance of picking up second-hand machinery which is worth having, as more proprietors of saw-mills come to grief ; but the difficulty is to find suitable machines when you want them, and the utmost caution is necessary when effecting a purchase. CHAPTER VIIL MoOTIVE-POWER—GENERAL REMARKS. THE motive-power is about the most often neglected item in the erection of a saw-mill. It is certainly the exception, rather than the rule, to find a plant of wood-working machines being driven really economically, for the simple reason that people are tempted to buy the cheapest power they can get ; thus saving a few pounds, or, perhaps, a few hundred pounds, at the start, at the risk, and in some cases the certainty, of losing many hundreds, and, per- haps, thousands of pounds in the long run, by a continual and daily waste of fuel, which can never cease until the works are closed, or the motive- power changed. Such people shut their eyes to the fact that every unnecessary shovelful of coal which is put into the fire-box of a boiler is so much money deliberately thrown away; and it is, perhaps, because the loss is doled out in shovelfuls that they do not appreciate the extent of it. But waste of fuel, though a very serious matter, is not the only important evil attendant on inferior motive-powesi. An engine which does not run regularly—that is 48 How to Select Wood- Working Machinery. to say, which does not govern properly—will be pro- ductive of the very worst results, both as regards the quality of the work turned out by the machines, and in the increased wear and tear of the machines themselves. Wood-working machines demand a more perfectly governing moter than almost any other class of machinery; not only on account of the very varied demands for power in a saw-mill, occasioned by the machines being continually and suddenly thrown in and out of gear, but principally because of the very high speeds to which some of the saws and cutter spindles attain. For instance, a very ordinary speed for a planing machine spindle is 4,000 revolutions per minute ; we will assume that the speed of the crankshaft of the engine driving it is 100 revolutions per minute. In such a case every variation of one revolution of the engine will effect a difference of 40 revolu- tions on the cutter spindle. Let us suppose that the engine governs badly, and that sometimes, when a pressure of work comes suddenly on, it is checked to a speed of go revolutions, and that, when relieved of the work, it overruns its normal speed by 10 revolutions, making 110 revolutions per minute. Such irregularity would affect the speed of the planing machine spindle to the extent of 8oo revolutions a minute, and the result would be bad work and injury to the machine. When running below its proper speed the work would be bad, and when running above it there would be undue strain on the working parts, and, consequently, the bear- Motive-power—General Remarks. 49 ings would tend to heat, and the spindles to bend or break ; in any case there would be undue wear and tear. Many a time a man has put down an excellent plant of wood-working tools, and crippled their action by employing inefficient motive-power ; and when he has found out that he cannot get satis- factory results from the machines, he has attached the fault to them, when it really lay with the motive-power. The accepted way of denominating the strength of any motor is by the term /Aorse-power, and, as this has but a vague meaning to any one who has not a smattering of mechanics, it may be as well to explain what it really does represent. A mechanical horse-power is a force which will lift a weight of 33,000 lbs. a foot high in a minute, or which will do an amount of work equivalent to that. That is all very simple enough, but the reason why people are misled is that there are three sorts of horse-power which are continually spoken of indiscriminately in business, but which by no means represent the same thing. These are :—1, Nominal power ; 2, Indicated power; and 3, Effective or brake power. The first of these, nominal power, means, at the present day, nothing—rz.e., it has no practical meaning from the purchaser’s point of view. In fact, it is only misleading, and is better left out of the question altogether. [Every engine-maker christens his engines whatever nominal power he 50 How to Select Wood-working Machinery. chooses. Thus some forms of engines indicate but little more than their nominal power, whereas others will sudicate more than three times as much. The power an engine will indicate, as got at by diagrams, or by a simple mathematical calculation, is a bond-fide force, and is easily arrived at and checked. It represents the gross strength of the engine, from which must be deducted the amount of power consumed by the friction of the working parts of the engine, and what accessories it may have, such as condensers, pumps, etc. The effective or brake power is the actual nett strength of the engine available for driving the shafting and machinery, and it is with this that the purchaser of motive-power should deal if he wishes to avoid complication. If engine and machines are ordered from the same maker, it may be assumed that the wood- working engineer will supply an engine of the requisite strength, but, if they are ordered sepa- rately, it should be ascertained from the manu- facturer of the machines how much effective horse-power they will require, and from the engine-maker should be obtained a guarantee that his engine will give out the required amount economically oz the brake. Let us suppose that a plant of machinery and shafting require, when working full, 100 effective horse-power, and that this amount of power would be required all, or most of, the day. It would not be policy to have an engine whose utmost limit was Motive Power—General Remarks. 5I 100 effective horse-power, as, if it were to work continually at that point, it would be straining itself, and probably wasting steam, and consequently fuel. Therefore the size of engine to buy under those circumstances would be one whose most economic working-point was at about 100 effective horse-power. ; On the other hand, if the machines in question seldom worked simultaneously at their full power, and consequently, as a rule, only required, say, 75 or 80 horse-power, the engine capable of giving off 100 effective horse-power, as a maximum, would possibly be about the right size (such an engine would probably be called by its manufacturer a 30 or 35 mominal horse-power engine ; but, as before stated, it depends entirely on who the manufac- turer is). ; : : The three practical forces for driving machines of this class are steam, water, and gas, for although many others have been suggested, and in some instances employed (for experimental purposes, or under exceptional circumstances), such as wind, hot air, electricity, and both brute and human animal power, yet they are not worth considering here. The largest concern that I have come across where this class of machinery was to be driven by actual animal power was a colonial mill which was designed, at the proprietors wish, to be worked by relays of twenty partially wild horses, shut in a circular enclosure, and harnessed to a sort of capstan, and driven round and round by a man ‘52 How to Select Wood-working Machinery. stationed on an elevated platform in the centre. It looked well enough on paper, but I never heard whether it resulted in a success. I should think probably not, as it would be difficult to regulate the speed. : ; Although the term “ nominal ”” horse-power must be considered as without definite meaning, when purchasing an engine ; it is as well to point out, as nearly as one can—and it can only be done approxi- . mately—the relative proportions which the nominal and effective horse-power bear to each other in different classes of motors, as the expression * nomi- nal” power must continually crop up in conversation about engines, and in catalogues. When horse-power is spoken of in connection with water-power, it invariably means the power of the stream. From this must be deducted the loss of power occasioned by driving the turbine, or water- wheel. Fixed steam engines will indicate from 100 per cent. to 250 per cent. more than their nominal power. The indicated power of portable and semi- portable engines seldom exceeds zoo per cent. more than the nominal power, and frequently it does not reach that limit. Gas engines, in many cases, do not indicate more than 4o per cent. above their nominal strength, though some of them, when quite new, are stated to be capable of indicating about twice their nominal power. CHAPTER IX. MOTIVE-POWER—STEAM. STEAM is, of course, the ordinary power in vogue for driving saw-mills, as for other machinery, for although both water and gas have certain advan- tages over it, yet it possesses qualities which more than make up for any deficiencies, in the majority of cases ; and the most prominent and valuable of its advantages is that, in localities where it would be impossible to use either water or gas-power, a steam engine can, in nine cases out of ten, be used. For instance, if a saw-mill is put up in a forest, or remote part of the country, there will be no gas supply, and consequently a gas engine cannot be run, and as for water-power, it is only when a sufficient head of water is provided by nature on the required spot that it is available for use. So much has been written about the steam engine that it would be out of place, and a waste of time to go into details as to the construction of the very numerous types in use at the present day. The - same rules apply to engines for working wood machines as to those employed on other work ; but, as before mentioned, it is of more importance to have a perfectly governed engine for this class of E ST TR Ty Ar 2 54 How to Select Wood-working Machinery. machinery than for most others, on account of the high speeds of the machines and the suddenly varying demands for power on the engine. To the purchaser it is merely a question of obtain- ing the engine which will do his work best, at the minimum amount of expense and trouble to him- self. I will therefore, confine my remarks on the subject to pointing out the results to be looked for from different classes of engines. If a saw-mill is to be run continually, for, say, more than twelve months in one spot, and requires more than, say, 10 or 12 horse-power to drive it, a high-pressure horizontal fixed engine and boiler should be employed for it, unless it is situated in a spot to which it is difficult to bring anything heavier than a portable engine. This engine should be fitted with what is known as automatic expansion gear, in order not only to save steam, and consequently fuel, but also to ensure’ a more regular speed to the engine than would be possible with the ordinary throttle valve. The automatic expansion, acting directly as it does on a variable cylinder valve, admits only exactly the amount of steam required, for, being itself actuated by the governor, it feels at once the varied requirements of the machine for power, and imparts them at once to the valve, cutting off the steam at different points of the stroke tc suit the demand. The minimum cut off should not be at more than one-third of the stroke of the engine, A throttle valve will not answer quickly enough Motive-power— Steam. 55 to its governor, as by the time the valve has opened to its full extent the demand for power may be gone, and, consequently, the engine, which, when the power was first required, began to slacken speed considerably, will, when the valve is wide open, “run away.” This has the disadvantage, besides being injurious to the work and to the machines, and wasting steam, of being very dangerous to the men employed, as it is productive of accidents ; and as employers’ liability at the present time is no empty responsibility, it is as well to take every pre- caution in this way. I have seen heavy pieces of machinery lifted from their foundations, and thrown considerable distances, owing to the sudden “racing” of a badly governed engine. With an ordinary throttle-valve engine it is im- possible to do full justice to wood-working machinery, so that under no circumstances should one be bought for this purpose. At the same time, if there happens to be one already fixed in a saw-mill, and the proprietor does not see his way to change it, there are many contrivances to be had now which will make them run with more regularity, and effect a considerable saving in fuel. One of the most practical of these, especially for slow speed engines, is the Proell automatic expansion apparatus.” ; The effect of it is to convert an engine with an invariable “cut off” into an automatic expansion engine, effecting thereby a regularity of speed and an economy of steam impossible otherwise, Reverting to the horizontal expansion engine, 56 How to Select Wood-working Machinery. this should be fitted with a suitable condenser, if sufficient water can be obtained (say twenty or thirty times as much as is required for feeding the boilers) without much expense or trouble, for although the condenser, with its pump, will absorb a considerable quantity of motive-power, this will be a small matter as compared with the great saving in fuel it will effect, as an engine of this description should not consume more than 4 lbs. of coal per indicated horse-power per hour, which equals with ordinary coals in London about 23d. per horse- power per day of ten hours. To effect a greater economy of fuel than the above it is necessary to have a compound engine (z.e., an engine with high and low-pressure cylinders), which must also embrace all the above-mentioned - advantages, and with such an engine the consump- tion of fuel should not be more than from 2 to 2} Ibs. of coal per horse-power per hour. I do not mean to say that all compound engines, by any means, will give such results, but the purchaser should take care to ascertain by guarantee what amount of coal, or other fuel, it will consume. But the amount of fuel per horse-power is by no means entirely a question of the type of engine alone, for, naturally, the boiler must have a great deal to do with it, and the above estimates of coal consumption are based on the assumption that the boilers which supply the engines with steam are of a practical and economical form. The compound engine, then, being the most economical one to work, it is, perhaps, extra- Motive-power—Steam. 57 ordinary that comparatively few are used for driving saw-mills ; but they have their drawbacks, and the principal one, or, at all events, the one which weighs most with the average purchaser, is the price, which is naturally considerably in excess of that of other steam engines. Another, and what I consider far more important, objection to them is their complication, which, owing to their high and low-pressure cylinders, and other details in their construction, is necessarily considerable. This is not of much importance where mechanical skill is easily obtainable, but, as in many cases this is not the case, it becomes necessary to have an engine of simpler construction, and which, while giving tolerably economical results, will not be liable to get out of order in such a way that it cannot easily be put right. When I say that in many cases mechanical skill is not easily obtainable, I mean such skill as would be able to repair a complicated engine ; for there is usually someone attached to a saw-mill who under- stands the machines, and can keep them in working order, besides having a general knowledge of the steam engine and its parts ; but it is the exception, rather than the rule, for such aman to bea finished engine fitter, and, as the engine is the heart of the entire saw-mill, every unnecessary minute that it is kept standing still is a very great loss to the master, and often to many of the men. In many mills enough sawdust, chips, and waste wood are made to suffice to feed the boiler without using any coal at all, and under such circumstances 58 How to Select Wood-working Machinery. economy of fuel is not so necessary as it would be if coal were used ; but it must not be forgotten that, in many localities, there is a good and im- proving market for sawdust and waste wood, so that it does not do to reckon, even then, that one gets one’s fuel for nothing. Vertical fixed engines are no longer used to any extent for this class of work, as, although they take up less ground space than horizontal engines, they are more expensive to fix and more difficult to get at when running, besides being liable to more vibration. For driving one or two small machines a little vertical engine, with vertical boiler attached, will answer its purpose well enough, and take up very little space, but it will be very wasteful of fuel, and be as much trouble to stoke as a fixed engine and boiler of three or four times its capacity. Portable and semi-portable engines are too waste- ful of steam, and their boilers wear out too rapidly to be recommended as a rule, but they have to be employed sometimes ; for instance, in temporary mills in forests, and elsewhere, and on estates where they are used for agricultural purposes during part of the year and in the saw-mill for the remainder. Whatever form of engine is adopted, an apparatus for heating the feed-water should certainly be used and will prove very economical. ‘ The boiler to be preferred under ordinary circum- stances for feeding a fixed engine is, if there is plenty of room for fixing it, one of the * Cornish” or “Lancashire” type, with * Galloway” tubes across the internal flue, and it should be made of mild steel Motive-power— Steam. plates. If wood refuse isto be burnt, the heating surface should be considerably in excess of what is usual for coal-consuming boilers. This form of boiler has the advantage over others of price and simplicity, and it is very durable. When once “set,” it can be stoked and looked after by tolerably unskilled labour, so long as the man is careful with his fire, his pressure, his water-level, and his blowing off ; and care taken to clean it out as often as the nature of the water used requires it. Equally good results are obtainable from a t Galloway's Patent Boiler,” which would take up considerably less space than an ordinary Cornish boiler of the same capacity, but would cost more. Where space is limited a * water tube " boiler of the “Root” type can be used to advantage. Though expensive in the first instance, it will pro- bably take up less than half the ground space of an ordinary boiler, cost less to fix, and much less for transport, especially on board ship, as it can be sent in small pieces, and consequently can be shipped at the ordinary machinery rates, obviating the exorbi- tant freights charged on other kinds of boilers. It is also claimed for it that it is absolutely safe from explosion, which is a very valuable quality. It is urged against it that its tubes are given to leaking, and from time to time they undoubtedly will ; but they can be readily and inexpensively replaced, as the tubes are interchangeable, and if one does not happen to have any spare tubes in stock, the boiler can be run without the faulty tube—with only the loss of heating surface caused by its absence—until it 60 How to Select Wood-working Machinery. is replaced by a new one. No boiler-maker is required to replace tubes, as they are but merely connected together by cast-iron connecting caps at each end of the boiler. In fact, these boilers are the direct opposite to the locomotive type, for the water to be generated into steam circulates inside the tubes with the former, and round the outside of the tubes in the latter case. ST IS) NX NS F1G 1.—RooT’s PATENT BOILER, The engraving (Fig. 1) represents a boiler of this Motive-power— Steam. 61 firebox and flues, the water inlet, and the form of setting. The effective horse-power which a boiler of any sort gives out is determined by the pressure it is worked at, the amount of steam it will generateina given time, and the condition of the steam (whether wet or dry) when it leaves the boiler. It isa gene- rally accepted rule that a boiler of a given nominal horse-power shall be capable of evaporating a cubic foot of water for every horse-power per hour, at 2a temperature of 212 degrees. But so much depends on the class of engine to be driven, and other extra- neous circumstances, as to how much of this power will be lost before it is transmitted to the machinery, that it is necessary when buying a boiler (if the makers of the engine do not also supply it) to ascer- tain how many feet of steam, at a given pressure, the engine will require for its work ; and then to arrange with the boiler-maker to supply a suitable one. It is a great mistake to overtax a boiler, that is to say, to work it at its full capacity, as by so doing it will be burning proportionately far too much coal, and wearing itself out unduly. For economy's sake, therefore, the boiler should be capable of generating at least 50 per cent. more steam than the engine requires, and it will be none the worse if considerably larger. type, showing clearly the position of the tubes with their connections, the steam drum at the top, the CHAPTER X. MoOTIVE-POWER— W ATER. WATER is undoubtedly the cheapest power to utilise, when it can be obtained, as it has the won- derful advantage over steam and gas of requiring no fuel, and again the wear and tear of the working parts of a water wheel or turbine compare favour- ably with those of an engine. It is impossible to say how its first cost will compare with that of any other power, as that will depend on what facilities may exist for adapting the water to one’s purpose. It possesses, however, two other qualities which give it a considerable advantage over steam, and they are :—1st, that it requires no stoker, or other attendant, except to stop and start it, and :—2nd, that it can be started at a minute's notice without any delay such as is required for getting up steam. Of course the most important of the above-men- tioned advantages is that it requires no fuel; and this alone is enough to make it obvious that it is policy to adopt it in preference to either steam or gas, when- ever it exists in a sufficient and reliable quantity for one's purpose. However, unless it is an absolute certainty that enough power will exist all the year Motive-power— Wadler. 63 round, or during such part of the year as it may be wanted, it becomes a question at once as to whether the loss occasioned by an inconvenient stoppage of the mill during a busy season would not outweigh the economy occasioned by its requiring no fuel. In such a case it may be worth while to have an engine on the spot capable of driving the whole, or a portion, of the machinery when required. These uncertainties have caused many millowners to discard their water-power altogether in favour of steam, rather than run the risk of stoppage of their works, even for a short time. It not unfrequently happens that a stream which during some of the winter and spring months would amply suffice for driving a mill, becomes in summer entirely dried up, or so diminished in volume as to be practically useless. On the other hand, it often occurs that a stream _ which, during the warmer part of the year, is cap- able of giving out plenty of power, gets completely frozen up, or diminished by its tributaries being frozen, in the winter. As an extreme instance of this, we may take the stoppage of the Niagara Falls, which took place on the 3oth March, 1847, and was described in the Niagara Mail as follows: —* The 620,000 tons of water each minute nearly ceased to flow, and dwindled away into the appearance of a mere mill-dam. The rapids above the fall disappeared, leaving scarcely enough on the American side to turn a grindstone.” I have no doubt that some allowance must be made 64 How to Select Wood-working Machinery. in the above account for Yankee licence, but, at the same time, it serves to give an illustration of the uncertainty of water-power. The cause of the above F1G. 2.—ALLEN’S TURBINE DRIVING SAW-MILL AT A DISTANCE. phenomenon is explained as follows, in another journal, at about the same date :—* This unex- pected event is attempted to be accounted for by an Motive-power— Water. 65 accumulation of ice at the lower extremity of Fort Erie, which formed a sort of dam between Fort Erie and Buffalo.” The conditions of the stream and falls, and other local considerations, determine whether it is policy to adopt a turbine, or water-wheel, which are the two ordinary mechanical appliances for converting a head of water into motive-power of a practical form. As a rule a turbine is preferable to a water-wheel, as it usually costs less to start with, besides making the most of what power there is, z.., it will trans- mit it to the shafting and machinery with less waste, and revolving, as it does, at a much higher speed than a water.wheel, a great deal of intermediate gearing and shafting required by the latter to get up the necessary speeds for the machines is done away with. Again, its working parts are much lighter, and do not consume so much power in friction. Fig. 2 shows a saw-mill being driven in an inge- nious manner by a wire rope, set in motion by a tur- bine, some distance away, as arranged by Messrs. W. H. Allen & Co., of Lambeth ; a system which permits the selection of the most favourable spot in the vicinity for the erection of the mill, instead of having it on the water's edge, which is often very inconvenient for many reasons. Sometimes it is thought that the form of stream lends itself better to the adoption of a water-wheel than of a turbine, but this is seldom the case ; for although it is a popular notion that the latter requires a deeper fall than the former, it is a mistaken one, as special turbines are now made which will 64 How to Select Wood-working Machinery. in the above account for Yankee licence, but, at the same time, it serves to give an illustration of the uncertainty of water-power. The cause of the above FIG. 2—ALLEN'S TURBINE DRIVING SAW-MILL AT A DisTANCE. phenomenon is explained as follows, in another journal, at about the same date :—* This unex- pected event is attempted to be accounted for by an Motive-power— Water. 65 accumulation of ice at the lower extremity of Fort Erie, which formed a sort of dam between Fort Erie and Buffalo.” The conditions of the stream and falls, and other local considerations, determine whether it is policy to adopt a turbine, or water-wheel, which are the two ordinary mechanical appliances for converting a head of water into motive-power of a practical form. As a rule a turbine is preferable to a water-wheel, as it usually costs less to start with, besides making the most of what power there is, 7.e., it will trans- mit it to the shafting and machinery with less waste, and revolving, as it does, at a much higher speed than a water.wheel, a great deal of intermediate gearing and shafting required by the latter to get up the necessary speeds for the machines is done away with. Again, its working parts are much lighter, and do not consume so much power in friction, Fig. 2 shows a saw-mill being driven in an inge- nious manner by a wire rope, set in motion by a tur- bine, some distance away, as arranged by Messrs. W. H. Allen & Co., of Lambeth ; a system which permits the selection of the most favourable spot in the vicinity for the erection of the mill, instead of having it on the water’s edge, which is often very inconvenient for many reasons. Sometimes it is thought that the form of stream lends itself better to the adoption of a water-wheel than of a turbine, but this is seldom the case ; for although it is a popular notion that the latter requires a deeper fall than the former, it is a mistaken one, as special turbines are now made which will 66 How to Select Wood-working Machinery. work well with a fall of 4ft., or even less. The efficiency, however, of the short fall turbines is pro- portionately much less than in those which are made for longer falls, say 15 to 30 ft., between which depths they are found to give the best results, transmitting to the machinery as much as 70 to 75 per cent. of the power of the fall. As regards water-wheels, an “ overshot ” wheel is preferable where there is a sufficient fall for it to be used, as over 6o per cent. effective horse-power can be obtained with it, whereas an undershot wheel will rarely transmit more than 30 to 35 per cent. of the power of the fall to the machinery, and a breast- wheel will give but slightly better results. In some cases the stream will not admit of anything but an undershot wheel, or a breast wheel, being used ; thelatter form being most serviceable for a very short fall of water. Therefore, when studying the question of water- power, it is not only important to find out whether there is an ample supply all the year round, but also what form of turbine or water-wheel will give the best results, under the circumstances, with the least trouble or unnecessary expense. The best means of ascertaining these pointsis to fur- nish the constructing engineer with a correct plan and elevation of the stream and its surroundings, at the locality where the wheel or turbine is to be placed, and showing the floor level and position of the proposed or existing saw-mill, together with a detailed description, giving the speed and direction of the current, the depth of the fall , the nature of I SNS sais Motive-power— Water. 67 the ground, and any local peculiarities that may affect the necessary calculations. If the would-be purchaser can give the amount of the volume of water passing over the “sill” per minute, some of the above details will be unnecessary. CHAPTER XI. MoOTIVE-POWER—GAS. Gas engines have for some few years been coming considerably to the front for all sorts of work, but for driving wood-working machines their use is but limited, and must necessarily always be so, for their cost, in the first place, is, at all events, no less than that of an ordinary steam engine and boiler of like capacity, but their wear and tear is greater, and their fuel vastly more expensive. For, as pointed out in a former chapter, an ordinary expansion con- densing steam engine should give out af least one effective horse-power for every 4 Ibs. of coal per hour, which would represent in London about 24d. per day of ten working hours, whereas it may be reckoned that a good type of gas engine will require some- where about 30 cubic feet of gas per hour per effec- tive horse-power, which would represent very nearly a shilling per horse-power per day of ten hours. Even the gas engine's two cardinal virtues, viz.— (1) that it requires no stoker or other attendant except to start and stop it, and (2) that it can be started without any preliminary getting up of steam, are not sufficiently weighty to counterbalance the great cost of fuel, except in the case of small 69 plants of machinery. For although the larger sizes of gas engines do not consume proportionately so much gas as the smaller ones, yet the difference in the cost of fuel between steam and gas is represented by a much larger figure as the amount of horse- power is increased. Besides which the utilising of chips and sawdust, &c., for generating steam, which reduces the coal bill considerably, and sometimes brings the cost of fuel for a steam engine down to practically 7:7, cannot be of any service in cheapen- ing the fuel for a gas engine. In a factory requiring 20 effective horse-power, a gas engine would, if employed, cost about £1 per day for fuel ; whereas, if a steam engine were used, and nothing but waste wood and chips burnt, there would be only the stoker’s wages, say 5s. per day, and the water, which would be a trifling matter. Supposing, however, nothing but coal was used, the cost would be (calculated as before) 4s. 2d. per day. This would show a saving in favour of the steam engine of 15s. a day when burning refuse wood, and 10s. 10d. a day when burning all ceal. This is assuming that the wear and tear, and other running expenses, in the two engines are equal. It may be urged that the labour of carrying the fuel to the boiler should be reckoned as an additional expense incurred by steam power, but, whether steam or gas is used, the saw-mill must be cleared, and the refuse carried somewhere, so it will probably work out cheaper to take it to the boiler, and burn it, than to cart it farther away. For driving a few machines, however, which do ¥ Motive-power—Gas. 70 How to Selest Wood-working Machinery. not require much power, a gas engine will answer the purpose very well ; and again it is useful in a factory where the machines are only required to be run spasmodically, for a few hours a day, or for a few days a week. It also takes up less room than a steam engine and boiler, and is much cleaner. Again, it can be used in places where, from local restrictions, or other causes, a steam engine may not be put down. For instance, owing to their lightness, there are many gas engines working quite satisfactorily on a second or third floor in crowded neighbourhoods; whereas a steam engine and boiler must necessarily be fixed on the ground floor to give practical results. Although I have taken thirty cubic feet of gas to represent an effective horse-power in an hour, there are several engines which do not give anything like this result, whereas some have shown better results than this at trials ; but it must be borne in mind that gas varies considerably in quality, as well as in price, in different towns, but it may be taken as the approximate average consumption of a good engine working at its most economical point. Some important patents, which in the course of a few years will lapse, are now held for gas engines, but after that time there will necessarily be a great drop in their price, and the improvements will be more rapid, owing to increased competition. Both the above eventualities, when they take place, will tend to make gas a more serious rival of steam for this class of work. Motsive-power—Gas. 71 At the same time, there are two or three gas engines running each other tolerably close now, and there has been a good deal of legal and journalistic warfare recently, between the different makers, as to the merits of their respective engines ; and reliable trials have lately been, and are still being, carried out, which tend to show that great progress is going on in this branch of mechanics, and which prove that" the gas engine is no longer a monopoly in the hands of one firm, which, until quite recently, had been practically the case. When thinking of buying a gas engine, all the above points should be carefully weighed, and a guarantee should be obtained from the maker as to the gas consumption per horse-power. It will be found that some engines will get more wasteful of gas as they are driven nearer their maximum limit of power, while for others it is claimed that they donot. In any case, it is as well to reckon, in a general way, that they should not be driven regularly at much more than their nominal power. = i —— Ee at ————— — spin A ————— RSS Sepuiiasis oE————————— a r Jokes ———_ CHAPTER XII. THE FuncTioNs oF WoOD-WORKING MACHINERY, IT would be out of place here to trace back the history of the various wood-working machines to their origin. Not only are the statistics which are to hand absolutely unreliable in most cases, but they would prove uninteresting to most people. England and America both claim to be the inven- tors of most of these machines, and, no doubt, sometimes one is justified in its claim, sometimes the other, and, very often, neither. I have seen a dozen articles in journals of different languages on the “First Band Saw Machine,” the “First Rack Bench,” &c., all telling different tales. I have known many men who styled themselves the * ori- ginal inventors” of machines which were certainly well known before they were born. Therefore, as these pages have nothing to do with ancient history, but deal exclusively with machines of the present day, I will confine myself to saying that, whatever the original machines were like, those of the present day “have, in most cases, but little in common with them, and that, consequently, we have to thank, not only the “ original inventor,” whoever he may have been, but alsa two or three generations of mechanics who The Functions of Wood-working Machinery. 73 have spent their lives in improving on the primitive designs. The questions which really interest the purchaser are :—To what pitch of perfection has such and such a machine arrived at? and where can I get it ? and at what price ? To answer these questions it will be necessary to deal with each class of machine separately, but before doing so, it will be as well to group them according to the work they have to do. An American writer groups them under four headings, as follows : 1. Machines acting by scission. 2. Machines acting by paring. 3. Machines acting by combination of these two. 4. Machines acting by abrading. : To use nearly his own words :—* The tools acting by scission are those which sever the fibres of the woods, reducing the material in their path to a fine dust. The second class, which acts by paring, would include those which produce shavings or chips. The tools of the third class must have a spur or saw-segment to sever the fibres ‘before the chisel edge can pare away neatly the material to be removed. The machines acting by abrasion, or grinding, in- clude sand-paperers and the like. These, however, are secondary. It is the saw and chisel of the handi- craftsman which furnish the basis of all the wood- working machines. The plane, the gouge, and the bit are themselves deductions from the primary two. The sand-paper and the file are the originators of the abrading machines.” 74 How to Select Wood-working Machinery. To go more into detail, wood-working machines for general work may be classed as follows :— Tree-felling machines. Log-sawing machines, in which are included various forms of cross-cutting saws, vertical and horizontal frame saws, mulay saws, band saws, and circular saws, with rack, chain, and rope feed. Deal-sawing machines, which also include cross- cutting saws, frame saws, circular saws, and band saws, of a smaller description, and of somewhat different construction to the preceding. Sawing machines for variety work, such as small band saws, fret saws, and certain forms of circular saws. Planing and moulding machines, among which are those with fixed and rotary cutters, which latter include, besides the four-sided moulding machines, trying-up machines, surfacing machines, hand planers, and irregular moulding machines, for curved and recessed work. Combined machines of the “ general joiner” type, capable of doing a variety of operations separately or simultaneously. Lathes for all kinds of work, plain and automatic, for copying, oval turning, &c., and rounding ma- chines. Mortising, tenoning, and boring machines of the vertical and horizontal class, acting by rotation, or reciprocation, or a combination of the two. Dovetailing machines of various kinds. Sand-papering and finishing-off machines. Labour-saving appliances, such as log-haulers, The Functions of Wood-working Machinery. 75 crabs, dust and shaving collectors, steam-niggers, &c. ; Machines for sharpening and setting saws and cutters. : Besides the above, there are hundreds of machines for special requirements, which it would be impos- sible to enumerate in detail here, or to class under any of the above headings, such as machines for cooperage work, veneer-cutting, sleepers, wheel- wrights’ work, bobbin-making, lucifer-match, Wools pulp, wood-wool, cane-splitting, &c., but some 0 which will be touched on in due course. It is not my intention to deal in this book with machines worked by hand or foot-power, as they can hardly be dignified by the name of machines at all. There are, it is true, * hand-mortising machines,” and ‘ hand-mitreing machines,” and “ foot lathes,” which fulfil their respective duties satisfactorily enough, when there is no other motive- power available. But for operations such as sawing and planing, I should say that, as a rule, it is money thrown away to invest in so-called “hand-power machines” for the purpose, as they show no real economy over the bond-fide hand tools. As regards what are known as machines for esther hand or steam power, 1 would point out that, on the face of it, they cannot be practical, for they must either be constructed in too heavy a manner to be actuated conveniently by hand, or their working parts must be too light and shaky to stand the regular wear and tear to which a steam driven machine is of necessity subjected. dion pig oe HS re — —— Si —— a ect E————— a BMS SHAY Seopa —— so i RA htt CHAPTER XIIL Tree FELLING. In the conversion of wood, whether by hand or mechanical means, the first operation must of ne- cessity be the felling of the tree. To effect this by the latter process, there has been a vast number of inventions, but owing to the difficulties of making an efficient tool sufficiently light to be conveniently carried about, they have nearly all turned out worthless. For, although there has been no lack of machines which would cut down a tree in less time than it could be done by manual labour, still the saving of time effected during the actual cuz has been more than counterbalanced by the delay and labour incurred in shifting the machine into the required positions. There would be no difficulty in making a machine to fell trees, if one could first of all bring the tree into the most convenient position for operations, as can be done with a log or plank; but as, for obvious reasons, this cannot be, it must be taken for granted that unless a machine for tree-felling is very light, and can be easily fixed, it is worse than useless. In England a tree-felling machine could never Tree Felling. 77 be used to great advantage, as people do not cut down trees in a sufficiently wholesale manner to warrant the moving of the necessary tackle from spot to spot. But in what are known as Zmber countries tree-felling machines are worked at a very material profit. In spite of the fact that these tools are not profitable to work in Great Britain, I cannot very well pass them over entirely, as this work would not be complete without some remarks upon them ; besides which many English firms have inquiries from abroad, and from the various colonies, for them ; and some of my readers will doubtless live outside Great Britain. A description of the variety of inventions which have been launched, or partially launched, for this purpose would be both interesting and amusing, would space admit of it here, but it will not. There is hardly a country where machinery is manufactured in any quantity which is not father to a tree-felling machine of some sort or other. I have seen designs of every imaginable type, driven in every imaginable way. One continen- tal firm of engineers used to issue an illustration representing a tree-feller worked by electricity, the electro-motive force being generated by a dynamo, propelled by a waterfall some distance off. It made a pretty picture, but the difficulty which naturally suggests itself to the practical mind is that of getting a ready-made waterfall in the re- quired locality. Other machines have been designed to be actuated by horses and other animals; and again 78 How to Select Wood-working Machinery. there is an American machine, where an engraving represents the operator sitting, smiling, on a sort of cross-bred rocking horse, the saw blade being actuated by the motion of his arms and legs. One would almost think that he would get through, at all events, as much work by using an ordinary hand-saw, for by so doing he would obviate the extra friction of moving the working parts of the machine, in addition to the saw blade. I believe this machine was intended more for cross-cutting the fallen tree than for the actual felling, but it would probably be of about the same value for the one operation as for the other. Another machine is represented as being worked by a long endless rope, driven by a portable engine, and passing over several guide pulleys, before arriving at the tree- feller, but this seems to me to present two substan- tial difficulties : 1st, the moving about of a portable engine—weighing some tons—in virgin forests, and mountainous or swampy localities ; and, 2nd, the finding of suitable points to which the guide pulleys for the rope may be attached. Fig. 3 is a sketch from a painting of a Russian machine for tree-felling, which will serve to convey an idea of the grotesque extent to which some of these inventions are carried. At first sight, it is difficult to understand how this machine is supposed to act, and, as a matter of fact, it could not really work at all ; but the inventor’s notion was, appa- rently, that the rotary motion imparted to the machine by the two operators should be greatly increased by the multiplying gear, so that the crank “ANIHOVJ]Y ONIT1Z] AU] ¥Od NOISAQ Nvissny—'§€ ‘013 (yoe3S eurSuo jo Spwmisoy) Ayah he wh PROUT Tre [oHD w 80 How to Select Wood-working Machinery. to which the connecting rod of the saw blade is attached shall revolve sufficiently rapidly. The saw is supposed to be fed through the tree by means of a weight attached to a cord, and the only visible means of steadying the machine is an ordinary screw, such as one might use to screw into a plank, at the back of the machine, but apparently intended to be screwed into the ground itself, which, how- ever, could not possibly hold the apparatus steady. Fig. 4 represents the only tree-felling machine which is at all in general use, and it is employed to considerable advantage in Russia, Roumania, Austria, Sweden, India, China, Japan, Borneo, Australia, Canada, and South America. It has been invented now some ten years, but it is only comparatively of recent years that these machines have been adopted on a large scale, which was due to the prejudice which existed against tree- fellers in general, on account of the numbers of unsatisfactory machines which had previously been brought out for that purpose. This machine, which is of English origin, weighs about 3 cwts., and can consequently be shifted from tree to tree without too much difficulty. It is its own engine, and the steam is supplied through a flexible steam pipe from a very light vertical boiler, on wheels. Consequently the number of trees which can be felled without shifting the boiler is determined by the length of the steam pipe and the proximity of the trees. It is naturally of the great- est importance to shift the boiler as little as possible, for, although it is sufficiently light for one horse to “ing stumps left behind Tree Felling. draw it about on or- dinary ground, still forest ground is often anything butordinary, and, althoughthistree- feller will work equally well on any slope, it cannot do so if the ground is too bad for the boiler to accom- pany it. Nor can it be worked in localities where water for the boiler is unobtainable. This tree-feller has the advantage over hand work of cutting flush with the ground, if required, so that there are no project- NDOMO1 S334 ATTEJ-AAUL, ,, WVALS INALVd—'Y *O1d when clearing a forest. This allows vehicles topass over theground on which the trees formerly stood, besides saving several cubic feet of timber from what is often the best part of the tree. The construction of the machine is as follows :—It possesses a steam “ 82 How to Select Wood-working Machinery. cylinder and piston, with the saw blade attached to the end of the piston rod. The saw is not strained in any way, but the action of the cross- head is steadied by guide bars, and its reciprocating motion actuates a twist bar, which works the steam valves, somewhat on the fire engine principle. The saw is fed through the tree by means of a hand- wheel at the back of the machine, worked by the operator’s right hand, while with his left he regulates the steam inlet, according to what he feels is required by the depth of the cut. The machine is held to the tree by a trident fork at the end of a bar, which passes under the machine, and is made fast by a couple of blows with a sledge hammer, and, as the teeth of the saw are arranged to cut only during the drawing in stroke, every stroke tends to fix the machine more firmly to the tree. The makers claim that, with four men to see to it, it will do as much work as thirty woodmen. The four hands required are as follows:—One to operate the machine, one to drive wedges in the cut to prevent the saw from binding, one to stoke the boiler, and one to carry wood and water. Care should be taken to place the machine on the opposite side to that on which the tree will fall. By the side of the boiler is a platform to carry the feller, steam hose, sledge hammer, &c., also a water tank, so that the complete plant is on four wheels which is a great convenience. By the employment of a triangular stand, this tree-feller can be tilted up on its side, so as to be Tree Felling. 83 used for cross-cutting the fallen trees into suitable lengths. The value of this machine has been attested lately, by its being copied in the United States, in which country the patent had been allowed to lapse. I have had occasion to witness this machine working on a great variety of woods, of all sorts of dimensions, and I certainly think that it gives the best results when working on hard wood trees of about 3 ft. in diameter. It does not matter much how hard the wood, is as it seems to make but little difference to the cutting, for I have seen it working with equal results on English oak and on South American quebracho, and it may be taken as an approximate calculation that this machine will fell a 3 ft. tree in four minutes. Soft wood trees of small diameter are so rapidly and cheaply felled by hand that the saving by machi- nery is not so marked, and inany case it is necessary to study the nature of the ground, and the quality and position of the timber, before investing in tree- felling machinery. CHAPTER XIV. HANDLING Logs AFTER FELLING. WHEN the trees have been felled, and cross-cut into the required lengths, and their branches lopped off, the next thing to do is to get them to the saw- mill, where they are to be converted, in as inexpen- sive a way as possible. To effect this is easy enough if railways and water- ways abound in the neighbourhood of the felled trees, but where such is not the case the expense of carting the timber from the forest to the port, or whatever destination it may have, often enhances its cost to such an extent by the time it arrives that there is no market for it at a profitable price, although the timber itself might originally have cost very little. Although in some cases it is policy to have a saw- mill in the forest where the trees are felled, it is not always practicable, and sometimes it is not even desirable, as, although by converting, or partially converting, the timber on the spot the waste wood can be left behind, and the transport thereby con- fined to the serviceable part of the timber, yet there is the expense of converting it to be put against this. Again, handling a large number of small pieces is Handling Logs after Felling. 8s sometimes as expensive as handling a smaller number of heavier pieces. Besides which, logs can be handled much more roughly, without damage to them, than is the case with planks, as the former may be jolted and bumped about with comparative impunity, whereas sawn timber should not have its surface knocked about; or even made dirty, if it is possible to prevent it, as grit is one of the worst enemies of planing cutters. Nor must it be forgot- ten that thin planks when green, and exposed t> all sorts of weathers and temperatures, will warp, twist, and shake at the ends, thereby losing much of their value. The ways in vogue for transporting logs vary a good deal in different localities: In England and other countries where the timber growth is insignificant, and railways intersect the whole country, the time-honoured ‘timber jim ” serves its purpose well enough for shifting logs ; but in timber-growing countries it is necessary to adopt some system which will deal with them in a much more wholesale manner. Water is, of course, the most practical means of conveying logs long distances when it happens to be in the required locality, for it is the cheapest, effecting its work, as it does, almost automatically, though very slowly. In Sweden, Norway, and elsewhere, logs launched into a river far up in the country are allowed to find their own way down to their destination, sometimes taking a year or two to effect the journey. In places where practical waterways do not exist, G Sn A BE ais St sm BE a sl As ——AH AE 86 How to Select Wood-working Machinery. hundreds of miles of railway have been constructed for no other purpose than to bring the logs from the forest to a port, or to some place where they are to be converted. In no country, however, is the system of handling logs so perfect as in Canada and the United States ; the “log driving” in Ontario, in the former, and Michigan, in the latter country, being one of the best organised industries in the world. Many thousands of men are employed at this work, which is carried on, briefly, as follows :— In the winter the logs are piled up to a height of sometimes so ft. on the frozen river, where they remain until the thaw sets in, when they naturally become immersed. However, nature, that is to say the stream, is not sufficiently strong without artificial assistance to carry away this huge mass of timber, which would simply get jammed and remain stationary, and so the river above this point is dammed at a suitable spot on its course, and, from time to time, the head of water accumulated by the dam is let loose, occasioning a heavy flood, which forces a channel through the logs. Men stationed on the“ rollways,” as they are called, loosen the logs, and set them adrift down the stream, the banks of which are watched, so that any logs which may get hung up at bends of the river can be at once set going again. When they arrive at the main river, they are taken in hand by a * boom company,” whose duty it is to sort and deliver them to the parties they are consigned to, *ANIHOVJN ON1AVOTT ANV ONIQAIAS wvaLg—'S O14 88 How to Select Wood-working Machinery. There are, unfortunately, in existence very few mechanical appliances for the shifting of logs, but there is one in considerable use in America which should not pass unnoticed, as under certain circumstances it gives excellent results in the way of collecting and loading logs, and although it would probably not be of any use in England, it might be adopted to great advantage in many of our colonies and elsewhere. This apparatus is known as “ Butters Patent Steam Log Skidding and Loading Machine,” and is manufactured by a Michigan firm. It is fairly well represented by Fig. 5 and consists of a special form of winding engine with a vertical boiler attached, which actuates the travelling block in either direction by means of two revolving drums, one of which is used to wind the block with the log attached to the end of the line towards the skidder, while the other acts on a receding line and takes the block and empty line back into the woods for another log. A third drum works the line running through the stationary block for lifting the logs on to the trucks when the running block (or * travelling velocipede,” as the makers call it,) has delivered them within its range. . : It is assumed that a line of rail is laid right up to the centre of the space to be cleared, the skidding engine being run along the rails on a truck to its destination, and finally fixed close alongside the track, which is then, of course, utilised for the trucks which are to be loaded with logs. It is stated that an area comprised in a circle having a diameter of as much as 13,000 ft. can be cleared by this Handling Logs after Felling. 89 apparatus without moving the skidding engine. Trees of suitable strength and height are left standing at intervals of zoo ft. from each other, all round the circumference of the circle to be cleared, to each of which in turn the guy-rope is made fast, as the direction of the work is shifted. The delivery of the logs is always towards the centre, where the loading takes place, and where two trees are also left stand- ing, to which are attached the supporting rope and guide lines for the stationary loading block, as clearly shown in the engraving. In thickly timbered districts this machine cer- tainly effects a striking economy over ordinary labour, and its simplicity is also a great point in its favour. CHAPTER XV. HANDLING AND Cross-CUTTING LOGS IN THE YARD. A GREAT deal of time and labour can be saved by systematically organising the yard-work. Timber mills, if of sufficient importance, will, under many circumstances, profit by adopting some of the machines and mechanical appliances which exist for aiding hand labour in this respect. Heavy logs are often left in inconvenient parts of the yard, rather than put into the most suitable places; for the simple reason that their weight makes it too much trouble to move them, except just when they are required for the mill, by which time the space round them may have become so cluttered up with other heavy timber as to greatly augment the diffi- culty of getting at them. If the shape of the yard happens to be a straight, narrow strip, a rapid travelling overhead steam crane is the most effective method of handling the logs, as it can be readily brought to bear on any point within its compass, and has the advantage of being very easily steered clear of any obstacle which may present itself in the path of the log by moving to one side or the other of it. The gantry of this crane should be run from the entrance gate of the Handling and Cross-cutting Logs in the Yard. 91 yard right into the mill itself, so that it can not only bring the logs up to the mill, but also manipulate them inside it, and adjust them on the travelling tables of the rack-benches or saw-frames, as required. Small locomotive cranes are used to great advantage in large straggling yards, a line of rails being laid down so as to intersect the area covered with logs. As the crane, in the first instance, sorts out and piles the logs in their places, they naturally are all within its reach when they are required for the mill. With this system, as with the last-mentioned, only two men are required to work it, viz.,, one to manipulate the crane, and the other to hitch the logs on, and the amount of work it will get through will soon prove its value in any place where enough can be found to keep it tolerably regularly em- ployed. Both of the above machines, however, cost a good deal of money, and, for those who are afraid of the outlay, a cheaper mechanical contrivance exists ; which, although it does not serve for lifting and sorting the logs in the yard, will effectually drag them into the mill from a considerable distance. This “ Hauling Apparatus” (Fig. 6) is fixed in the mill itself, either on the floor or suspended from strong rafters, and consists of a strong winding-drum, actuated by belt-power. Three or four hundred feet of chain can be used, and either a hook, or timber clips, as preferred, serve for attaching the log. When it is required to haul timber otherwise than in a straight line, the chain is simply passed 92 How to Select Wood-working Machinery. round ordinary snatch-blocks made fast to the ground, at the apices of the different angles round which the logs are to be dragged. Where a mill is placed on the water's edge, and the logs are floated alongside it,a simple con- H®] F16. 6,—HAULING APPARATUS FOR LOGS. trivance for lifting them in consists of a pair of endless chains revolving slowly round pulleys, two of which are under the water, and the other two in the mill, the top ones being driven by a belt. At intervals along the chains are projecting dogs, which, Handling and Cross-cutting Logs in the Yard. 93 as the chains revolve, come in contact with the logs, and convey them into the mill, a man being stationed with a sort of boat-hook to guide them within reach of the dogs. This system answers admirably for sleeper mills, where it is necessary to handle a great quantity of small timber very rapidly. The hand cross-cutting of large logs in the yard of a saw-mill is also a very heavy item of expense, which goes to be alleviated considerably by the use of suitable machinery. There is a variety of tools for this purpose which can be recommended under certain circumstances. The difficulty, however, is that logs being very cumbersome things to move about, it would be an advantage to cross-cut them as they lie, so as to reduce them to their minimum weight before taking them into the mill, which is what is done when cross-cut by hand. What is wanted, then, is a machine which can be carried to the logs, whatever their position may happen to be, and can be set to work without any fixing. No machine actuated by a belt could effect this, as the fact of its being driven in that way limits its range to, at most, a few feet. The reciprocating steam cross-cut saw, briefly referred to in the chapter on tree felling, and fed by a flexible steam hose from the boiler, can be moved about by two men, and set at work anywhere within say sixty or eighty feet of the boiler, with good results. [t will be found of still more service if worked in 94 How to Select Wood-working Machinery. conjunction with a locomotive crane, as it can be fed by the crane boiler with quite a short pipe, being carried about on a platform made for it on the crane, and can be dropped down in position for working, and replaced on the platform by the crane itself, without requiring more than the two men who would, as a matter of course, be in charge of the latter machine. When the logs are brought up to the entrance of the mill, and deposited on a given spot, belt- driven machines can be called into operation to great advantage. Those working with a circular blade are the most rapid in action, but owing to the difficulty in working circular saw blades over 6 ft. in diameter, and also owing to their very high price, they are not to be recommended for cross-cutting logs of a larger diameter than from 2 ft. to 2 ft. 6 in. In the case of all cross-cut saws for logs it should be the saw which is fed through the wood, and not the wood pushed up to the saw ; consequently, circular cross-cut saws are fed automatically through the logs, and returned with a more rapid motion. In most of the designs of this class of machine the feed is horizontal, but one of the most practical forms that I know of is that shown by Fig. 7, where the feed is vertical. This machine is fixed altogether below the mill floor, so that, when not being used, a free passage is left at the entrance of the mill, the only sign that the machine is there being a long narrow slit in the floor. The log to be cross-cut is placed across this slit, the machine is set in motion, ; is al fav °u. TTT A r I Fi1G. 7.—CIRCULAR CROSS-CUT SAW FOR Logs. | 96 How to Select Wood-working Machinery. and the saw blade, rising through it, does its work and quietly descends below the floor. The unob- trusive, but effective, action of this machine is very interesting to watch, but care should be taken not to walk over the spot through which the saw blade makes its appearance at a moment when it is about to rise. For dealing with logs of larger dimension, what is known as a Reciprocating Cross-cut saw is pre- ferable to, though slower than, one of the circular type; in action and speed of work it resembles somewhat the steam cross-cut before mentioned, but is actuated by a belt from a shaft, instead of by a direct-acting steam cylinder. It is much less expensive, and takes a great deal less power than a circular cross-cut, besides which it can be arranged to cope with logs up to 5 ft. in diameter if required. CHAPTER XVI. RECIPROCATING SAw FRAMES. In European markets the frame saw must hold its own for many years as the leading all-round machine for planking either logs or deals, as it possesses several qualities which make it indispen- sable for this work, Compared with the rack circular saw, it does not take anything like the power to drive, and does not waste anything like the amount of wood per cut. But, on the other hand, it turns out its work very much slower. It has hardly occurred to people here to compare it with any other machine, as the band saw, which is now practically taking its place in North America, at all events for soft woods, is not reckoned as a serious competitor to it in this part of the world, though one of these days it may become so. The great variety of frame sawing machines which are now in the market, and which can be considered as practical at the present day, may be roughly divided into two classes, viz., those with a rack feed, and those with a roller feed. For rough and crooked, or very hard timber, and for deals of a greater width than 18 inches, as also for wet or frozen deals, a rack feed should be used. 98 How to Select Wood-working Mackinery. For timber of even growth, and for ordinary deal sawing, a roller feed is all that is required. There are many ways of adapting both rack and roller feeds, but as the remarks on feeds which apply to reciprocating saws apply equally to any other form of saw, the subject will be dealt with ina separate chapter. There is, however, one point which is peculiar to the feed of a reciprocating saw, and that is, that it must be intermittent ; and the proper way to obtain this is by means of what is known as the * Silent Feed.” It is true that some short-stroked deal frames are made on the Continent which have no provision for an intermittent feed, the result being that either the saw blades are unduly forced, or the rollers refuse to feed the deal regularly, and con- sequently the work is impaired in either case. Another reciprocating frame with an uninterrupted feed is that in which the saw blades are arranged with half the teeth pointing one way, and half the other, with a view to cutting on both upward and downward strokes, and so do double the work. The idea is ingenious, but unfortunately that is its only recommendation ; for the inventor, and those who have adopted it, seem to have overlooked the fact that as only one half of the teeth of the blade are at work at one time, the machine, though cutting on both the upward and downward stroke, does not get through more work than if cutting only on the down stroke with all the teeth set one way. The work, also, must necessarily be defective as pulling both ways causes the deal to rock more ERE Li Reciprocating Saw Frames. 99 or less, as its top and bottom surfaces are never quite true and parallel. The points to look for in the selection of a frame are the following :— 1st. The design of the swing frame.—This should be of steel, and as light as is compatible with its being strong enough to carry the requisite number of blades. It is often found, in the case of inferior machines, that when a certain number of blades have been hammered up tight in it, the sides of the frame will bulge out, and set it fast in the guides. In a properly constructed frame this should be impossible. 2nd. The side guides.—These should be adjust- able, so that they can be readily taken up in accordance with the wear on them. 3rd. Ze crank shaft should be of steel, and should be carefully counterbalanced. A bent crank is preferable to a disc or pin, except for very light work, as with it a bearing is obtainable on each side of the connecting rod. 4th. Zhe system of feed should be suitable to the nature of the work. sth. Appliances for holding the wood as steady as possible, when under the action of the saws, should be adopted. 6th. Access to the blades.—The design of the machine should admit of every facility for getting at, and fixing, these. 7th. Foundations.—The machine should not require these to be of too complicated a nature. 100 How to Select Wood-working Machinery. 8th. Vibration, when running, should be as slight as possible. It must be borne in mind that the longer the stroke of a frame the more work it will do per revolution of the crank shaft. On the other hand, the shorter the stroke the quicker the crank shaft can be run ; therefore, when buying, it is necessary to look into both these questions. Theoretically speaking, the length of the stroke should be just a little longer than the depth of the wood through which the saw is passing, so that each cutting tooth of the blade may appear at one or other end of the cut, thus allowing the sawdust to free itself after each stroke. It will be found, however, that a frame saw advertised as being capable of cutting to a certain depth will seldom have a stroke of that length. This is due to the fact that it is assumed that the machine will not always be sawing the maxi- mum size of log or deal. It is not so important to have a stroke of great length in the case of very high.speeded frames, as their quick action helps to free the teeth from dust. The rate at which a frame will do its work, and the amount of horse-power required to drive it, depend on the following conditions: — 1st. The design and construction of the machine. 2nd. The dimensions and nature of the wood. 3rd. The number and condition of the saw blades in use. By allowing the blades to run too long without Reciprocating Saw. Frames. "> 101 sharpening, or by using improper teeth, the power required to drive the machine may be greatly augmented. The swing frames should be tilted in such a manner that the teeth retire from the actual cut during the upward stroke. as—" Fic. 8.—LoGc FRAME, WITH OVERHEAD CRANK SHAFT. ‘Some log frames of the more complicated types are capable of receiving 40 or so blades at a time, but they have to be constructed on very strong and consequently heavy lines, which makes them very expensive. But it is seldom that so many cuts are required, and so the greater number of machines Hn A A Shige ip ————— Ll HI a aa Siem rs Aa Pr pe st le AS 5 Es 3 2h SNS ti SNE ——_—— ! - 102 How to Select Wood-working Machinery. are not reckoned to take more than say one saw blade to every inch in the width of the swing frame. Deal frames, however, should be capable of taking from four to five saws to the inch. The foundations of these, as of all reciprocating machines, are of necessity solid in construction, as the down thrust, occurring as it does some hundreds of times in a minute, causes a considerable shock to whatever is underneath the machine ; for however well-balanced its working parts may be, this cannot be altogether obviated. For this reason frame saws should never be fixed otherwise than on a ground floor or basement, unless a solid pier of masonry can be run up from the ground itself to the base of the machine. In the ordinary course of things the swing frame is actuated by a connecting rod, one end of which is fixed to its lower cross-head, and the other to the crank shaft below it. However, this plan necessi- tates a considerable amount of the working parts of the machine being below the floor, for which a certain space in depth becomes indispensable. This it is sometimes impossible to obtain, on account of the presence of water near the floor level, or from other causes. To meet this difficulty, the crank shaft and connecting rod may be placed overhead, as shown byFig. 8, which represents a frame designed by Messrs. Robinson & Son, Lim., of Rochdale, for this purpose. It will be seen thatin this case the whole of the machine is, practically speaking, above the floor, so that ali that is required in the way of Reciprocating Saw Frames. 103 foundation is a solid lump of concrete or brickwork, of sufficient strength to support the weight of the machine. It is, however, necessary to securely stay the machine at its upper extremity, as it would otherwise be somewhat top heavy, and vibrate too much. Another form of frame worked from overhead is that in which the crank shaft and its pulleys are 777777 Fi. 9.—PORTABLE LoG FRAME. replaced by a steam cylinder and its fly-wheel. This direct-acting steam frame can be recommended in cases where an ordinary engine of sufficient ca- pacity cannot be used, though it is somewhat costly. In the case of semi-portable frames, where simple foundations are also an advantage, a pair of light connecting rods, one attached to each side of the swing frame, are substituted for the single rod, so 104 How to Select Wood-working Machinery. that the crank shaft can be brought close up under the machine. For work in the forests, a portable log frame with roller feed, as shown by Fig. ¢ (by another English firm), is very suitable. The simplest way of preparing this machine for work is to dig a hole = I} { | [ |] i lo) FIG. 10.—BREAKING DOWN AND RE-SAWING FRrAMF. in the ground, of a sufficient depth to enable it to stand as shown in the engraving, the wheels resting on the bottom of the pit, and the trolleys which support the log running on rails laid on the ground level. The breaking down and re-sawing frame (Fig. 10) Reciprocating Saw Frames. 105 is certainly one of the most useful all-round machines in use for converting large timber, as the overhung saw blade can be either used for squaring the logs, which is usually the work of a circular saw, or it can take the place of a horizontal saw, for planking costly timber with a slow feed ; whereas the internal frame can be fitted with as many saws as are required for resawing the timber squared to its capacity by the outside saw blade. There being two racks to this machine, the two sides of the frame can be worked independently, and at different rates of feed. Another form of frame for coping with either logs or deals, and which is largely used by con- tractors and jobbing men, is one with a rolier feed. Its working parts are to all intents and purposes similar to those of the portable frame (Fig. 9), but the wheels are replaced by a suitable base plate. When it is required to work on deals, a simple apparatus is fitted to the machine, which enables it to cut two deals simultaneously. Horizontal log frames are used only for cutting hard and expensive timber, such as mahogany. They are costly machines, and do their work slowly, but they offer facilities for adjusting the log after each cut, so as to make the most of the valuable timber. To work satisfactorily, the crank shaft should run in bearings which are fixed to the main frame of the machine, The most rapid frame for sawing deals is that of the equilibrium type, that is to say, one constructed with two light-swing frames, worked from one J venom ov ae ee ra rer Rr a —— i 106 How to Select Wood-working Machinery. crank shaft, with two cranks placed in cpposite directions, so as to cause one frame to descend as the other rises, and so counterbalance each other. This plan enables a far greater speed to be attained than by any other system, and, in these days of working against time, it is undoubtedly the frame to adopt in any factory where there is sufficient work for it. It may be safely reckoned that the “ Improved Fraser Equilibrium Frame,” as represented by Fig. 11, will turn out 50 per cent. more work than any double deal frame of the ordinary type. It will be noticed that the feed is actuated by vertical smooth rollers propelling the deal on both sides. This is the best form of roller feed for any class of deal sawing ; as when fed on one side only, a fluted roller is necessary, which has the effect of spoiling one of the outside planks by making a series of indentations on it. Again, when fed by horizontal rollers both have to be fluted, on account of the small bearing surface which they get, and this dents both edges of the deal, and con- sequently each individual plank suffers. A double deal frame of the ordinary type would be in construction similar to the machine shown by Fig. 11, but it would have one wide swing-frame in place of the two light independent ones shown in the engraving. The lower portion, ze., the crank shaft and connecting rod, would be of stronger section on account of the increased strain occasioned by the extra weight of the heavy double frame. Swing frames should be speeded at, in the case of log frames, from 400 to 600 feet per minute, and in Reciprocating Saw Frames. 107 the case of deal frames, from 600 to goo feet per minute, half of which represents the cutting stroke of the saw blades. F16. 11.—IMPROVED FRASER EQUILIBRIUM DEAL FRAME. As regards the rate of feed, log frames are usually arranged to feed from 1 to 4 feet per minute, and 108 How to Select Wood-working Machinery. ordinary deal frames up to about 6 feet, while equilibrium frames are speeded as high as 8 feet per minute. It is, however, seldom that any frames are seen working at the maximum rate of feed even on soft woods; and the harder the wood the slower the feed. The number of saw blades in use in a frame should not influence the rate of feed, nor would it do so if there were sufficient horse-power behind the machine, and the system of feed were strong enough for all emergencies. However, in most mills it will be found that one or other of these points is wanting, or perhaps both; and the con- sequence is, in such cases, that the more blades there are the slower the feed must be. The shape and state of the saw teeth naturally have a great influence on both the quality and quantity of the output, and a man who thoroughly understands his work will be very careful about these matters. In this chapter I have enumerated some of the representative saw frames for general every-day requirements. There are, of course, an infinite number of others for special purposes, which space will not admit of my dealing with, such as Duplex frames, compound roller frames, single blade frames, of which the main parts are constructed of wood, horizontal frames, with vertical feed, double and equilibrium log frames, &c., all of which are useful for certain classes of work. But the observations that I have made, as regards the points to be looked for, may be taken to apply equally to them. CHAPTER XVII, CIRCULAR SAW MACHINES. WHERE waste of wood is of no importance, and motive-power is cheap, the circular saw, in some shape or form, is the best all-round tool to employ for converting timber, on account of the rapidity with which it does its work. In fact, even in this country, where neither of the above conditions holds good, it may be still considered the most popular sawing machine, as there are many more of them in use than of all other kinds combined ; in spite of their not being practical for either planking logs, or, as a rule, for ripping long stuff, in cases where more than one or two cuts are required. There are, however, so many operations for which they are pre-eminently suited, and, in fact, indis- pensable, that there is no danger as to their losing their popular position, at all events, as far as can be seen at the present day, The following general qualities should be possessed by circular sawing machines :— 1st. The bed-plate, or bench, as the case may be, should be formed of a massive and practically-shaped casting in one piece, so as so obviate vibration. 2nd. The saw spindle should be of steel, and fitted with long bearings to enable it to withstand 110 How to Select Wood-working Machinery. the strain occasioned by the belt, necessarily some- times very wide, and always fast running. One of these bearings should be close against the saw blade, and another just inside the driven pulley, whilst, whenever possible, a third should support the end of the spindle beyond the pulley. 3rd. Practical adjustments for guiding and pack- ing the saw blade, and proper provision for removing and adjusting it, without loss of time. The rate at which a saw blade will do its work is only limited by two considerations, viz., the power available for driving it, and the amount of forcing the saw will stand. The thicker a saw blade and the faster it is run the more work it will do per minute. On the other hand, as a saw blade gets thicker the necessary power to drive it increases very rapidly. It is an easy matter to make a rack bench absorb 100 horse- power, but it would not be easy to get any one over here to buy one, if he reckoned that he was going to use anything like so much power as that to drive it. The Americans habitually use much thicker saws than we do, with inserted teeth, and put no end of power behind them. The waste of wood is greatly in excess of what is usual with English machines, but they turn out more work than we do. I draw attention to this fact to show that it does not do to put the machines in the same category, as the requirements of the two countries being different, the saw-mill engineers construct their machines accordingly. OI] WAAWI], ONIIVAOS A0d HONIG MOVY—'ZI 112 How to Select Wood-working Machinery. What is generally understood here as an “ American” rack bench (not necessarily manu- factured in America) is one in which the travelling table is fitted with appliances for readily setting up the log for planking purposes, whereas the ordinary “ English " rack bench is not fitted with these, as it is intended only for squaring timber, or perhaps taking one cut down, and the additional adjust- ments add considerably to the cost. There are, of course, many other details in their construction which differ in the two machines, and to demon- strate this I illustrate by Figs, 12 and 13, typical benches of the two countries. Fig. 12 shows a representative English machine destined for squaring timber. The log is carried to the machine on a travelling table running on a series of turned rollers, and there is no provision but the weight of the timber for keeping it in posi- tion. This, however, is sufficient for the purpose when the machine is used for squaring. The machine is self-contained, as the apparatus for the feed and return motions is bolted to the under side of the bed casting. This should be stipulated for in buying a machine of this type, as it facilitates the fixing, by obviating piers to support this gearing, and by not requiring so much excava- tion. Fig. 13 is a bond fide American rack bench, built by the Lane Manufacturing Co., of Montpelier, and is largely used in the States. This machine can be fitted, or not, with the top saw shown in the engraving, as required. The feed motion "HONG NOVY AT4N0( NVOINAWY—'€I OI 114 How to Select Wood-working Machinery. is, in this case, above the floor level, and is (as with the last-mentioned machine) fitted to the bed-plate of the machine. The travelling carriage is fitted with sliding heads for adjusting the timber for planking. It is usual with such machines to place imme- diately behind the saw blade a convex wheel, or circular wedge, to keep the saw-cut open, and thus avoid side friction on the blade. The effect of the top blade, which is arranged to meet the saw-cut of the under blade, is to greatly increase the capacity of machine as regards the size of timber which it can deal with. In calculating the dimensions of log which a circular blade will cut, the maximum will be half the diameter of the blade, less the distance between the table level and the centre of the saw spindle. But in practice it will be found advantageous not to work it continually at its full depth of cut. It must also be remembered that every time a saw is sharpened, its diameter, and consequently its capacity, are somewhat reduced. Although circular blades are sometimes worked as large in diameter as 7 ft., and have been used up to 8 ft., they are not to be recommended for general use above 6 ft. in diameter. This would bring the maximum capacity of a single blade machine down to logs of something under 3 ft. in diameter. When, however, the machine is used only for breaking- down round timber, and is consequently never required to cut through the centre of the log, it may be reckoned that a blade of a given dimension Circular Saw Machines. 115 can be used for squaring logs of nearly half its diameter, provided they run tolerably straight. il, i 'qad,] ¥ovy aNVH HLIM HONAg MvS—¥I *Olf | . CTs Ni -~ By adding a top saw to a rack bench, a cut of from 4 ft. to 4 ft. 6 in. can be obtained. i : § | i ' 116 How to Select Wood-working Machinery. In Europe but few machines with a top saw are used, although at all events one English firm has been in the habit of making them for many years past, but mostly for export. The cost of grinding and tempering circular blades causes the price to increase very rapidly as the sizes get larger, and I have never come across a saw -maker who would care to guarantee the good working of a blade of more than 6 ft. in diameter. A cheap and simple circular saw bench is repre- sented by Fig. 14. This machine, which is con- structed by Messrs. Robinson & Son, Lim., of Roch- dale,can be used to advantage in shops where motive- power is deficient, as the rack feed, being actuated by hand, can be humoured to the capacity of the engine. When logs of uniform length, requiring one cut down the centre, are to be sawn, such as sleepers, a bench with an endless chain feed, and dogs at suit- able intervals, is the best machine to be used. A popular bench for all-round work, where some of the mate ial to be sawn is not heavy enough for a rack bench, and too cumbersome to be readily manipulated entirely by hand, is one fitted with what is popularly known as “self-acting gear.” The feed is effected by means of a rope or chain with a hook at one extremity, which the sawyer hitches. on to the end of the log or deal. By moving a lever, a revolving drum is set in motion, and the rope, or chain, is wound round it, thus drawing the material to be cut past the saw, whilst the sawyer keeps it up against the fence. There being no attachments on the saw table except the fence, the Circular Saw’ Machines. 117 bench can be used for ordinary work, without pre- paration. ‘SALVAVAAY ONIMVS IVA(J HLIM HONAH Mmvg—91 ‘O10 There are many adaptations of the roller feed to circular benches, and Fig. 15 represents a machine I RE AA ——— A Nc ihn» A — ps i AAO llr sl tn RE arson ———— — — = a a rr ———— ERAN LR = pep——— BE - 118 How to Select Wood-working Machinery. which can either be used as a plain bench, or for sawing deals with a vertical roller feed. The feed apparatus, which in the engraving is shown dis- mounted, can be readily fixed on the table. The feed rollers are carried on a pivoting arm and kept up to the deal by the weight shown, and are set in motion by gearing. They can be brought into position to suit saws of a different diameter, with- out loss of time. Fig. 16 illustrates an American ripping bench Fi1G. 16.—AMERICAN RE-SAWING MACHINE, with roller feed, known as a re-sawing machine, and manufactured by Messrs. Connell & Dengler, of Rochester, U.S.A. It will be noticed that the saw, which is of large diameter, is made up of segments with a view to getting a much thinner edge than would be possible otherwise with so big a blade. The saw is supported both above and below the cut so as to keep it steady, and this, combined with its large diameter, ensures good wok, and adapts it for cutting thin planks. A fixed wedge immediately Circular Saw Machines. 119 behind the blade forces the slab off the saw, relieving the latter from side friction. Fig. 17 is another bench with roller feed ; and having a self-centring adjustment is specially suited for taking one cut down a deal when it is important that it should be correctly divided. If required, however, two blades can be used side by side with a thicknessing collar between them. The feed is FIG. 17.—SELF-CENTRING SAw BENCH. powerful, consisting of four vertical rollers, two on each side. If planks of a given thickness are to be sawn, the rollers on one side can be set fast. so as to act as a fence. : A popular adaptation of the plain saw bench, and one which is very necessary for joinery work, is that in which the spindle has a vertical adjustment, enabling the saw to project as little, or as much, as 120 How to Select Wood-working Machinery. may be required, above the table, so that it can be used for grooving and rebating. Another means to the same end is a bench where the spindle has no adjustment, but the table rises and falls. The varying height of the table, how- ever, is apt to inconvenience the sawyer sometimes. An ingenious bench for light work, such as for pattern-makers’ requirements, is a combined ripping and cross-cutting bench. This machine carries two separate blades, each on its own spindle, and is so arranged that either can be brought above the table at a minute's notice, the same motion which brings the saw, to be used above the table, throwing the descending saw out of gear. It, however, should not be used for anything but light work. In circular sawing machines the fence plays an important part, and provision should be made not only for readily adjusting, and canting it to any angle for bevel work, but also for removing it without loss of time, so as to leave the table without obstruction if required. For certain work, where the wood presents a straight surface to the fence and the planks are not too thin, a series of free rollers on the face of the fence (as in Fig. 15) are used to advantage, as they obviate friction. On the other hand, it is often found that one side of a deal is rounding or bulging ; that is, it projects more in the centre of its width than towards its edges. Under such circumstances two iron strips should be bolted to the face of the fence, one just above the table, and the other near the level of the top edge of the deal. Circular Saw Machines. 121 When cross-cutting or mitre-cutting is to be done on an ordinary ripping bench, a longitudinal square groove should be cut in the edge of the table, into which can be fitted a suitable slide to ensure a straight cut. Circular saws should be speeded to run as follows :— Feet per minute on their teeth. Rack benches ... ... 9,000 to 10,000 Ordinary benches ... 10,000 ,, 12,000 Cross-cutting or grooving benches “re ... 12,000 ,, 13,000 The above rule can only be taken in a very general sense, as individual machines for special purpose are often governed by circumstances which modify it considerably. CHAPTER XVIII BAND-SAw MACHINES. As already stated, the use of the band saw for any purpose is far less general in England than in either America or on the Continent, especially for cutting round timber. English people have been in the habit of looking on it as unreliable for cutting straight. That alone has been enough to damn it as a machine for break- ing down or planking, as, although the actual saw- cut may be of less width than that of a circular, if it is apt to be thrown out of its proper course when encountering knots or irregularly-grained wood the waste is quite certain to be vastly greater than with another machine. Under such circumstances it would only be policy to use a band saw for curved work, which cannot be done by either circular or frame saws, and perhaps for a little straight cutting, when other machines were not to be got at,and that is practically all it has been put to in this country, except in isolated cases. That its services are underrated there is no doubt, but it is also equally certain that it will never be so generally useful here as it is abroad, and for the following reasons :— Band-Saw Machines. 123 1st. The band-saw machines for logs used in England up to the present day have mostly been of so imperfect a construction as to thoroughly prejudice people against them. 2nd. English saw-makers have not been success- ful in making band-saw blades equal to those of foreign manufacture. 3rd. There are, comparatively speaking, but few sawyers who thoroughly understand the keeping in order and working of band-saw blades. This last difficulty is one which would rapidly remedy itself were the opportunity afforded, as would be the case if the machines were more generally adopted. It is, however, a fact that the quality of the work of a band saw depends a great deal more on the sawyer than is the case with other sawing machines. I have never seen in England (that is to say in an English saw-mill) a band-saw machine for logs giving satisfactory results, although they sometimes seem to satisfy their owners. I once came across some rather good work done by one, but on going to see the machine I found 7 was never reckoned possible to work it at a faster feed than one foot a minute. That was at about one-twentieth the speed at which the same work might have been done in a frame, and about one-fiftieth of that of a rack bench. A properly constructed band-saw machine for logs would be a good deal more expensive than a rack circular saw bench, and, atall events, no cheaper than a frame. Its turn-out should be, roughly speaking, 124 How to Select Wood.- working Machinery. about two-thirds of the former, and considerably in excess of the latter. Its waste of wood per saw- cut should be but little more than that of the frame, and less than half that of the rack bench. It has one great advantage over the other two machines, and that is it can be made capable of dealing with very large logs without any material alteration to its construction. The size of the log it will take in is practically determined by the height above the table, to which the upper guide-box can be adjusted. But the larger the log the slower the rate of feed must be if good work is to be done, and it is by no means advisable to work a band saw regularly on anything like its maximum capacity of log. Its results as to speed of output and quality of work are both better in soft wood than in hard. I have chosen for illustration (Fig. 18) a band- saw machine manufactured by Messrs. E. P. Allis & Co., of Milwaukee, U.S.A., which is of very practical design and construction. This machine is capable of sawing upwards of 30,000 ft. of pine perday. To effect this a great deal of horse-power is used (from an Englishman's point of view), but then the result justifies it. The saw pulleys of this machine are 9 ft. in diameter, the bottom one weighing nearly a ton and a half, with alview to acting as a fly wheel, and so preserve a uniform speed to the blade under suddenly varying loads ; while the top pulley is constructed on the directly opposite plan, being made up almost entirely of wood, with flat spokes, fixed so as to offer as much resistance to the air as UNE ep REIN LULL DK N NN N NON F1G. 18.—LARGE BAND-SAW MACHINE FOR LOGS. 126 How to Select Wood-working Machinery. possible, and so act as a gentle but continual brake to the saw, and thus strain it tight in the cut. The ribbed cast-iron framing shown under the floor does not form part of the machine, but merely serves to show a suitable form of support for the bed plate, One of the most important points in a band-saw machine for logs is that of supporting the wheels properly, so that when the saw is tightened up it cannot spring them at all ; for if they are sprung, the blade cannot be run satisfactorily. With a view to effecting this, many makers place a bearing on each side of both top and bottom wheels, and although this adds to the cost of the machine, it is the most effective method. The expense caused by the breakage of saw blades has proved a drawback to the use of the band-saw machine for any class of work ; and it is often a great deal in excess of what it need be. With a goed blade, a good machine, and a good man, the breakage would be but a small item in the expense ; but, unfortunately, the absence of any one of these three conditions is quite enough to make the item for breakage augment incredibly. A few pence or shillings in the price of a saw blade should not be studied, for although a good man will sometimes get as satisfactory results from an inferior blade as an incompetent man will from a first-rate one, the life of a defective saw is certain to be a short one. In the ordinary course of things, when a blade has broken once, it means that it will keep on breaking, as it has probably been strained, Band- Saw Machines. 127 and weakened in a good many other places than at the actual break. Sometimes these weak spots are visible to the eye, and sometimes not, but as a rule they are there after the first break, and conse- quently the blade does not last much longer without breaking in another place. To prevent breakage of blades it is necessary that the machine should be practically designed and constructed. The main casting must be heavy and rigid so as to obviate all vibration. The saw pulleys must be of ample diameter, and carefully turned and balance, and tyred with indiarubber. The smallest diameter for a band saw pulley should never be less than 30 in., even for the lightest work. Where an automatic feed is used, such as for sawing small deals, or splitting oak staves down the centre, 42 in. is none too large for the pulleys. When sawing logs of small diameter the pulleys should be at least 6 or 7 ft. in diameter, and for large logs 9 or 10 ft. In any case it may be taken that the larger the pulley the better for the work and the blade. It is easy to make and advertise a cheap band saw machine capable of taking in a large dimension, as it is only a question of putting the pulleys far enough apart, however small they may be, the only extra expense to the manufacturer being a somewhat lengthened main casting, which would cost him a few 128 How to Select Wood-working Machinery. more shillings at the outside ; but such a machine would not give satisfactory results, as the pulleys must be enlarged proportionately to the work to be done. I have been told that at the present day there is, in England, a band-saw machine with 24 in. pulleys at work on logs 4 ft. in diameter, and cutting at the rate of an inch or two a minute. I have not seen it, and I hope I never shall ; but such an anomaly is only a somewhat striking example of the many worthless band-saw machines to be seen about. People used to put flanges on the back edge of the saw pulleys, with the avowed object of keeping the blade from being forced off them when cutting ; and although the practice has been given up, it is as well to point out that such flanges are not only entirely useless, but also very injurious to the saw blades ; for many such machines, though made some time ago, are still in work, and it would be as well to have the flanges turned off. If the saw blade does not run against the flanges there is no use for them, and if it does, they heat the back of the saw, and cause it to expand more than the front, detracting from the quality of the work and injuring the blade. The presence of such flanges is also apt to make the sawyer careless, as, knowing his blade cannot run quite off at the back, he does not always take the trouble to adjust his machine with proper care. The right way to regulate the position of the blade on the pulleys is by canting the top pulley in such a manner as to ensure its running as required, Band-Saw Machines. 129 and the adjustments for effecting this should be simple and easily got at. The packing or guide boxes must be of such a nature as to effectually steady and support the saw blade immediately above and below the cut, and the top box must be readily adjustable vertically to suit different depths of work. There are a hundred different methods of guide box in use at the present day, but they may be summed up under two head- ings, viz., those where the bearing surface is hard wood, and those where the bearing surface is metal. In cases where the machine, the blades, or the sawyer are not quite what they should be, the wood packings are preferable to the others, as, working under such conditions, either the saw or the packings must be sacrificed to undue wear and tear, and it is better that it should be the latter than the former, as the small pieces of wood can be easily and in- expensively replaced as fast as they wear out. But where a properly constructed machine is being run by a competent man, a metal packing can be used to advantage, provided it be arranged to support the saw rigidly without injuring it. The best apparatus of this sort is Mouw’s Patent Band-saw Guide, as shown by Fig. 19. The construction of this is as follows :— Both top and bottom boxes are of cast iron, and are adjust able backwards and forwards to suit blades of varying widths, as is easily seen from the engraving. The side guides are two rectangular strips of steel, also readily adjustable to suit blades of various widths, and set in position by means of thumb. 130 How to Select Wood-working Machinery. screws. They should be placed as shown, so that they support the whole width of the saw except E/ = Mouw's PATENT METAL GUIDE BOXES. TENTH 19. CTA) Fic. the teeth. This affords the. double advantage of not allowing the set to be rubbed off the teeth, and of Band-Saw Machines. 131 offering an uninterrupted view of the saw, as it enters the cut, to the sawyer. The back supports, which alone are subject to wear and tear, are formed of square strips of steel, of small section, placed immediately above and below the side guides, and at right angles to them. They are kept in position by a light spring, and can be pushed along in their grooves by the finger and thumb, so as to present a fresh surface, as required, if the back of the blade cuts them at all ; while, being square, they can be turned so as to present any one of their four sides to the saw. It will be seen that one of these backing strips is placed at the lower extremity of the box, and consequently, when the guide box is lowered as near to the work as possible, the back of the saw blade is supported immediately above its work. The blade being thus rigidly supported both on the sides and at the back, a great deal more work can be got out of it than would otherwise be the case, and, as it cannot swerve out of its course, the quality of the work is greatly superior. If deals and flitches are to be cut up by a band- saw a double vertical roller feed should be adopted (similar to that shown on the deal frame, Fig. 11, Chap. XVI), and the machine should be constructed specially for the purpose. Sometimes, however, a combined machine is required for both sawing curved work and ripping deals. When such is the case, a band-saw, as shown by Fig. 20,1s a sensible tool to adopt, as the feed apparatus is so arranged as to be readily removable, 132 How to Select Wood-working Machinery. leaving the table free for sweep cutting when required. All plain band-saw machines should have a cant- Fi1G. 20.—BAND-SAW FOR STRAIGHT OR CURVED WORK. ing table, so that they can do bevelled work, unless the top pulley is adjustable so as to cant the saw instead of the table. The last system is preferable for sawing heavy stuff, as the table forms a level Band- Saw Machines. 133 instead of a slanting bed for the wood, and thus it is not liable to slip. For light work, however, this is immaterial, as the wood can be readily kept in the required pcsition by hand. The great thing to be looked to in buying a band-saw machine is this :—Whatever may be the stated capacity of a band-saw machine, it by no means follows that it is suitable for doing anything like the maximum dimension given, and its practi. cal capacity is best determined by the diameter of its saw pulleys, bearing in mind the considerations laid down earlier in this chapter. # CHAPTER XIX. FRET-SAwW MACHINES, MacHINES for fret-cutting, or “jig saws,” as they are sometimes called, are the least popular of any class of sawing machine in use. Their only raison d’¢tre at all is for internal cutting, as for such work they are the only tools that can be used. For curved work, however fine and delicate it may be, a band saw should be used where possible, as it will operate with far greater expedition, and with every bit as much exactitude, as a fret saw, if it is a properly constructed machine, When, however, internal work is required, a band saw, being an endless blade, becomes unavailable ; and then it is that the fret machine must be employed. Fret-saw machines, though varying somewhat in details of design, and very materially in quality of workmanship, may be divided into two classes, viz. :~-1st, those with unstrained saw ; 2nd, those with strained saw. The former are for doing the coarser class of work, where a blade of a certain strength is required to cope with it, Such a blade will consequently be stiff enough to work without straining. Fret-Saw Mackines. 135 The second class, however, being used for delicate work, such as piano fronts, ornamental brackets, etc., requires as fine a blade as ‘it is possible to use. 777% Fi1G. 21.—FRET MACHINE WITH UNSTRAINED SAW. Under such circumstances it becomes necessary to strain the saw from above by means of a spring. As regards the principal parts of these machines, Z.e., the standard, the crank, and the table, the con- 136 How to Select Wood-working Machinery. struction of both types is practically identical ; the only difference being that those destined to work with unstrained blades are naturally somewhat stronger, and have a longer stroke, than is the case with the others. It is of great importance that the crank-shaft should revolve at a high speed, say 1,000 to 1,500 revolutions per minute, and consequently it must run in long bearings, and be well balanced and lubricated. It is also an essential feature that it should be closed in by a guard or box to keep it clean, and out of the operator's way. The tables of all fret machines must be readily cantable, as in the case of band-saw machines destined for bevel cutting. With unstrained fret-saw machines it is usual to suspend a guide from overhead, as shown by Fig 21. Tt will be seen the guide, which resembles somewhat the guide of a band saw, has a vertical adjustment, so that it can be raised or lowered to suit the thickness of the wood under operation. This arrangement of overhead suspension permits the working of long stuff, which would be impossible were it self-sustained, #.¢., fixed to an arm forming part of the machine itself. Fig. 22 is a fret-saw machine with strained blade, and cannot be called a very prepossessing machine to look at, on account of the somewhat heavy arm which supports the straining apparatus and guide. This heavy arm, however, is designed with a view to obviate any vibration, a point of cardinal import- ance when good work is to be turned out. Fret-Saw Machines. 137 The difficulty with strained saw machines has ever been to design a spring which is sufficiently sensitive to recover itself immediately, without any jerking or shocks to the blade, as it rises after each downward stroke, bearing in mind that there are some hundreds of reciprocations per minute. ee a Fi1G. 22.—FRET MACHINE WITH STRAINED SAW. The proper speed for a machine with a strained blade is 1,000 strokes per minute, as without such a speed the quality of the work and the rate at which it is done must both be below what they ought to be. All sorts and conditions of springs have been tried } 38 How to Select Wood-working Machinery. in connection with the strained fret saws—spiral springs, carriage springs, indiarubber springs, etc. —but they have mostly either been wanting in sensitiveness, or they have not been lasting enough to be really satisfactory. In the case of the machine illustrated, the spring is composed of two long wooden rods, held fast at one end by an arrangement attached to the main casting. The top of the saw-blade is clipped to one end of a stout leather band, the other end of which passes round a portion of the circumference of the small pulley above the blade. This pulley is so connected with the rods that the latter (their extremities being drawn somewhat together) form a spring, which tends to keep the pulley stationary. The descending action of the crank pulls the blade downward, causing the small pulley to make part of a revolution, and as the crank lifts, the action of the pulley in question is immediately reversed by the tension of the rods as they regain their former position. With this spring very good results have been obtained, as by the length of the arms a practically uniform strain is exerted throughout the stroke, and a very high speed is attainable. When very long work is required to be done, the whole straining apparatus can be suspended from above, if required, but an inferior class of spring must then be used. However, this is not often necessary, as the more delicate fretwork is seldom cut in very long lengths. CHAPTER XX. CROSS-CUT SAW MACHINES. CRrOss-CUTTING machines are so nearly akin to other sawing tools that it is impossible, when deal- ing with ripping machines, to leave them always out of the question. Consequently, on referring back, mention will be found of certain types in Chapters XIIL, XV, and XVII. The general features to be looked for in selecting cross-cutting machines are also practically identical with those of ripping saws, as already set forth, but a cross-cut saw should always be considered as a special machine, that is to say, it should be bought expressly with a view to the work it will have to do. Too often there is a tendency to make use of an existing, though unsuitable, machine for this work, rather thaninvest in a suitable one, with the inevitable results of bad work and waste of labour. A circular saw, which is destined for ripping, does not, as a rule, run anything like fast enough to be effectively used for cross-cutting, so that, if it is essential to use one machine for the two purposes, the spindle should be furnished with two speeds. In practice, however, it is found that it is a mistake to run one spindle at different speeds, as it is bad 140 How to Select Wood-working Machinery. for the bearings ; consequently, a combined machine =—== should only be used in cases where there is not sufficient work to warrant separate ones. For crosscutting large logs, the reciprocating steam saw, and the cir- cular saw with vertical range, referred to in Chapters XIII. and XV. respectively, cannot be surpassed ; but for small logs, which can be par- tially or entirely manipu- lated by hand, a pendulum saw (Fig. 23) is a useful and expeditious tool. It is also largely used for cross-cutting planks of any ordinary dimensions, and its simplicity, the little space it occupies, and its moderate cost, are all points in its favour. It is usual to suspend this machine from a rafter, as shown in the engraving, the overhead shaft which drives the blade forming the pivot on which the Ther Fic. 23.—PENDULUM CROSS- CJT SAW, Y 2 pendulum arm, which carries the saw, swings. Cross-cut Saw Machines. 141 The upper portion of the saw is protected by a guard, to which is attached, in a convenient position, a handle for drawing the saw through the timber, which latter is placed on a table constructed of wood, and arranged to a suitable height under the saw. For heavy or long planks it is usually policy to keep the material stationary, and let the saw pass through it, as with the pendulum cross-cut saw. Fig. 24 shows a plank cross-cut saw of American Fi1G. 24.—CROss-cUT SAW WITH TRAVERSING BLADE. construction. In this case the blade, which is actuated, as far as its revolving movement is con- cerned, by a countershaft at the back of the machine, is pulled through the wood by the hand-rod shown above the bench, and the belt is kept at a proper tension, whatever the distance of the saw spindle from its countershaft, by the tightening pulleys under the table. Fig. 25 represents an improved design of auto- matic machine, of English make, for cross-cutting heavy scantlings, deals, planks, etc. In this machine, z < wn Ee 2 © | on 1 «© Oo i == oO re] 4 = — | P = = < = CS I 2 I vy N $ 2) - Cross-cut Saw Machines. 143 as its name implies, the saw advances through the wood automatically. This movement is set in motion by the hand lever on the right of the illustration, causing it to make one cut and retire to its position at the back of the table ready for a repetition of the operation, when the lever is again brought into requisition. When it is a question of sawing light stuff, the advancing and retiring movement can be made continual. Two of the great advantages possessed by this machine are : First, that the sawyer has both hands free for the manipulation of his wood ; and second, that the saw being actuated by a quarter-twist belt from a countershaft below the floor, the natural position of this machine finds itself at right angles to that of the ripping machines, which is as it should be, as the planks cross-cut at it will not have to be turned before being taken to the other machines, which constitutes a great saving in labour and space required in the mill for their manipulation. A popular cross-cutting machine in North America is the “Emery & Garland Lumber Trimmer” (Fig. 26). It will be seen by the engraving that a number of circular blades are placed in a row, one of which is at a considerable distance from the rest. This single saw, which has no adjustment, is for trimming off one end of each plank. The other blades are placed at varying distances from it, each one corresponding to a standard length of lumber. The four saws are mounted on independent spindles, each on a hinged arm, or tilt frame, which enables the saw to rise 2 = = = ~ b= | ot =