Book_Mn___ CoifyrightN?_ COP^tRIGIfr DEPOSm Coremaking COREMAKING By DR. RICHARD MOLDENKE COMPLIMENTS of CORN PRODUCTS REFINING COMPANY New York Copyright 1918 CORN PRODUCTS REFINING CO. All rights reserved OCT l8l9iB ©CI.A506230 To the Foundry men: So many of the losses in the Foundry due to imperfect castings can be laid to core-room practice, and so little has been done to study the several determining factors which are important for the perfect core for the work in hand, that we have sought to obtain for foundrymen authoritative informa- tion bearing upon core-room progress. To this end, we secured the services of Dr. Richard Moldenke, of international reputation in foundry work, to make a line of tests with various core-binders, sand mixtures, baking temperatures, etc., to aid the foundryman in judging the material he buys and in using the same most effectively. The article presented herewith deserves the careful attention of all foundrymen. To make the booklet of additional value for reference, a collection of tables is included giving informa- tion useful, but frequently not at hand in convenient form. It is hoped that this publication may fill an existing need, and serve to awaken interest and investigation. Respectfully, Corn Products Refining Company. ^'-Z yit^"^ Coremaking by Dr. Richard Moldenke ONE of the retarding influences in manufacturing enterprise is the ever present tendency to sacrifice quality to quan- tity production. This condition is noticeable in every line of business and is the cause of dissatisfaction and pecuniary loss to an extent but little realized. Every one interested thinks him- self che one specially selected as the victim. A manufacturer of molding machines who is honest enough to guarantee say one hundred and fifty molds, in figuring on a prospective order, will find himself in competition with a rival guaranteeing six hundred in equal time on his type of machine. The careful man loses the order and the foundry- man, by the time he puts the remains of the over-rated machine in his cupola, fervently wishes he could put the builder in with it. No one is satisfied and all have lost out in some way. The foundryman should not so much want to see a beautiful park of molds ready for pouring when the blast goes on, as that every one of the molds made will turn out a satisfactory cast- ing. This pays in the end, and obviates the constant squabbles with molder and customer over imperfect work. Good Castings The elements entering into the making of a good casting may be summed up as follows : Good metal and fuel into the cupola ; perfect melting and molding practice; good sand, cores, and above all proper gating; with these arranged for, the results should pass muster. A molding sand is good when of uniform grain size, the bond a fat refractory clay, and carrying a mini- mum of fluxing impurities. When properly tempered with water and judiciously rammed it forms a safe container for the molten metal. For greater resistance to the pressure and cutting action of the molten metal a mold may be dried. The strength of the sand structure goes up at once, the chances of failure from sand troubles diminish and the castings are more readily machinable. The Core A core is a body of sand placed in the mold to form a corre- sponding cavity in the casting. From this it will be noticed that 3 COREMAKING whereas the mold proper consists of compressed sand surround- ing the molten metal poured in, the core is in the reverse situa- tion; namely, a body of compressed sand almost entirely sur- rounded by molten metal. The sand surfaces of the mold allow the gases emanating from the setting metal, as well as the steam generated in the sand itself, to escape. In the case of the core, however, any steam or gases formed through contact of the molten metal with component parts subject to decomposition, must either be given free venting through the core itself to the atmosphere or else these gases will "kick" back into the metal and form a "blow," ruining the work. Core Sand The character of the sand used for a core must, therefore, be far more open than that for the mold itself. Indeed, small cores are usually made of sand free from all clay bond, and in the larger ones molding sand is added for the purpose of strengthen- ing the core body. Since not more than a third of the core- mixture for large work may be molding sand, and even this of coarse structure, the strength of the result will be still far below that of the molding sand itself unmixed with sharp or fire sand free from bond. Imagine adding twice as much sharp sand to one of the sand-heaps on the molding floor, mixing thoroughly and then attempting to mold with this. If it is at all possible to hold the copes from dropping, the corners and edges of the mold will be quickly washed away by the molten metal in pouring. The Binder Nevertheless, for purposes of affording a sufficiently quick and safe exit for the gases through a core, this must be made of very open sand; clean, round, uniform-sized grains which cannot be packed together sufficiently to close up the spaces between them being most desirable. Manifestly, such a sand could not be held together without an added binding material strong enough in character to require but little of it so that the venting power of the core be not interfered with. The nature and method of applying such binders in core-making will be gone into more fully further on. Attention should be called at this point to the unusual strength requirements of cores as against those of the mold itself. The Mold The compressed sand of the mold is firmly held in wooden or preferably iron flasks provided with all kinds of cross- bars and similar devices to hold the sand in place before and COREMAKING during the filling of the mold with the molten metal. This metal would then exert a pressure within the mold tending to compress the sand still further (swelling the casting) and also to lift the cope. It is naturally assumed that the cope is clamped tight upon the drag and that the entire flask is strong enough to resist deformation of any kind. The ferro- static pressure of the molten metal is a very patent thing to be reckoned with, as every molder who makes his first stand- ard test bar mold will know. The bar is V/i" diameter and IS" high — the bar being cast vertical with top pour. Usually the first few bars come out looking more like Indian clubs than the nice straight cylinders they should be. The sand of the lower portion of the mold has been compressed that much in addition to the regular ramming up by the molder. In the core the foundryman nas usually to deal with the powerful buoyant action of the molten metal exerted on long, comparatively thin-sectioned horizontal bodies of sand im- bedded in the sides of the mold. Unless such cores are made of exceptionally strong sand and binder mixtures, and are in addition provided with heavy iron rods, they may readily bend upward in the centre or even break in two. The selec- tion of the sand to be used and the core-binder to be added, therefore, is a vital issue in the foundry and to which the foundryman cannot give too much attention. Sand Characteristics So far as the sand is concerned, the ideal one is composed of round grains of equal size, these grains well finished by nature so that they may resist the action of heat without splitting up or crumbling. The finer the grain size, the smoother the surface the core will leave. On the other hand, the finer, the less the venting power. Hence the foundryman should select the finest grain he dare safely use. For large cores this means very coarse sand, even shading into fine gravel. Where the portions of the core which are imbedded in the mold to hold it in proper position are ample for good venting, the addition of molding sand is advisable, as this not only adds strength to the core but also may save bmder — clay being nature's binder and far cheaper than any manufactured product. In most foundries the molds when shaken out yield so many large coreprints that it is necessary to use them over in the mixture in sheer self-defense — to hold down the bills for removal of the foundry dump. Core mixtures, therefore, are usually made up of core-sand (more or less free from day 4)ond) , molding sand, and old cores which have been COREMAKING crushed up. To these mixtures there is added the core- binder. Cores are always made with the mixture in the damp state, the binder being either a liquid, such as linseed oil, or liquid binders thinned down with water, such as molasses- water; or dry binders mixed with the comparatively dry sand mixture, and then wet up to bring out the adhesive qualities of the binder. After ramming up the cores they must be baked. This operation consists of two distinct steps; first the actual drying, or evaporation of the water content, and then the baking proper. This gives the core its desired strength and removes as far as possible the component parts subject to destructive distillation when the molten iron touches it. The gas-making parts of the core being thus removed, there iS still a final destruction of the binding substances required from the continued contact with molten iron, for the core must crumble and be easily removed from the recess it has formed in the casting. Core Requirements The service requirements of a good core may be summed up as follows: — It should stand up well enough in the green state to enable safe handling for baking. It must not swell or crack during baking, or soften and deform in storage within a reasonable time. The binder originally evenly dis- tributed throughout the core should remain so and not draw to the skin sufficiently to endanger the result. A core should not soften, deform or "blow" during contact with molten iron before this has had time to set. It should crush easily after the casting has cooled and be readily rapped out. Cores must be well vented, and are best not set into the mold unless this is pretty certain to be poured the same day. Molds that have been closed up and are not poured off should be opened up next morning to examine the cores for moisture, as these — ^particularly with binders requiring water to moisten or dilute them for use — are prone to re-absorb it if not changed in character by thorough baking. Classes of Core Binders The core binders in general use may be classified as follows: Water-soluble binders Paste binders Colloidal and allied bodies Gums and Pitches Oils The foundryman ordinarily, hov/ever, classifies the binders as dry and liquid. COREMAKING Binder Characteristics The more important of the water-soluble binders are mo- lasses, "hydrol" and the neutralized and concentrated waste sulphite liquors of the paper pulp process. Molasses is known to everyone. "Hydrol" is a syrup having the same relation to corn sugar that molasses has to cane sugar. The material on the market today should not be confounded with a former imported product ("hydrol" — oil soluble in water) which gave very poor and uncertain results as a core binder. The treated sulphite liquors above mentioned are much used in coremaking in conjunction with clay and other binders, and for their strength depend upon the soluble vegetable resins contained. The fact that the resins form but a very small part of the material accounts for the poor results obtained in the tests described later on when used with clean sand. The binder shows up better with molding sand additions. In general, these binders are good so far as their adhesive properties are concerned, as in drying they draw to a point between the sand grains and thus cement them together. The two objections to the entire class, however, are the tendency of the binders to draw to the skin, leaving a weak interior, and the softening of the cores in damp places and within molds. The introduction of colloid substances, such as clay, counteracts the migratory tendency of the binder somewhat, and hence the use of molding sand in the core mixture. Softening of Cores The softening of the cores is a serious problem, for not only are lost castings to be reckoned with, but the storage of surplus stock becomes impossible. The difficulty is aggra- vated where the core-storage room is damp, of stone or con- crete and apt to condense moisture from the air. Actual tests have shown that the trouble may be overcome by a proper baking of the cores. Underbaked cores will soften. On the other hand, overbaked cores are weak, and it there- fore becomes a question of good core ovens and attention to the temperatures maintained in them. The driving off of the water in the soft cores requires time, but after this has been accomplished the baking itself is not a very long process. Core ovens on the down-draft principle work best. The core plates are put in near the bottom under the influence of the hot gases and air sweeping downward. The moisture is thus driven out and carried away in the bottom flues and up the stack. When dry the cores should be put into the upper part of the oven where the temperature is higher and be given the additional heat treatment to bake them well. If COREMAKING the temperature of the lower portion of the oven be ke-> not less than 250 degrees F. and the upper regions (or in the case of linseed oil cores at 475 degrees satisfactory situation will be maintained. These temperatui can be raised somewhat if the men are alert enough to tal out the cores when properly baked. This hastens the proces. Prolonged baking, however, under these conditions producei. burnt and therefore weak cores. In the tests to be described later, the broken cores were placed in a very damp cellar with concrete walls and floor. The underbaked cores were all affected more or less by the existing dampness, some of them flattening out badly. Where the maximum safe drying temperature had been reached, how- ever, and where overstepped a little, the cores remained per fectly dry and safe to use in the mold. This indicates tha complaints about the core room can be obviated to a con siderable extent, if not entirely, by proper attention to th.. oven construction and baking process. Paste Binders The paste binders are among the oldest and best knowr. of all. Flour is still the old stand-by in many shops, but ha the objection that unless sparingly used the cores will swell Further, in baking, the acrid smoke evolved is almost in supportable where the ventilation is poor. The development of this class of binders has, therefore, run in the direction ot separating the essential binding principle from the inert parts of the cereals used, and putting this concentrated adhesive material into the dry binders of commerce. Probably the best of all dry binders are those having £ dextrin base. When properly manufactured and proportionec these binders are so strong that but little is required in th^ core mixture and hence in baking the smoke and annoyance, incident to the use of flour in poorly designed ovens, is done away with practically altogether. To utiUze these binderr to the fullest advantage the core-mixture should be temperec up in the afternoon previous to use. This will thoroughly soften the binder and allow it to spread evenly and thinl> between the grains of the sand, giving much of the effec obtained with the water-soluble binders. A second mixing in the morning completes the preparation of the batch anc breaks up all lumps, leaving a fine uniform mbcture for tht work in hand. The disadvantage of the group is the tendency to draw moisture if not properly baked, though not to as serious an extent as with the water-soluble binders. The growing de- S COREMAKING .mands upon the core room, particularly when larger classes H' work are made necessary by the advent of the jarring . chine and molds made up almost entirely of cores, must •'Vcsult in greater attention to this rather neglected foundry department. Among other things, cores will be baked at proper temperatures after the moisture contained has been entirely removed, so that they do not come out with hard, brown surfaces and a soft interior. Attention will also be given to blacking materials so that the carrying medium may incidentally act as a protection along the lines of water- proofing. In the meantime, however, foundrymen should see that the core-drying capacity is well ahead of their require- ments, so that the work need not be rushed unduly. Other Binders The Colloidal bodies derive their binding power from the glue or jelly-like constituents they contain. Clay is the best of them. Manure, magnesia, aluminum and iron compounds find their application in some measure in foundry specialty work. But after all, clay fills the bill best and its presence in molding sand makes this the desirable medium for adding strength to the core mixture so long as the venting power of the finished core is not interfered with too seriously. The Gums and Pitches are best represented by rosin for the first named, and the tars entering the so-called black com- pounds for the latter. Rosin, when melting, will run about the grains and cement them together on cooling. As it does not bind the core when green, other substances must be used. Clay may be sufficient, but usually flour or a better grade paste binder has to be added to the mixture to enable the use of rosin at all. The constantly rising cost of the gums is steadily making them too expensive for coremaking pur- poses. The pilches are particularly good for the larger classes of cores, but as they carbonize under the influence of molten iron they give much difficulty in the cleaning room. This has, therefore, to be reckoned with when using them in sufficient quantity to give satisfactory results. The best representative of the oil group is Linseed Oil. It is rarely obtained by foundries in the pure state, but is adul- terated, if not entirely replaced in many instances by other cheaper vegetable and mineral oils. The fact that this oil de- pends upon a rapid oxidation of the thin films covering the sand grains for its binding power emphasizes the necessity of a thorough circulation of hot air in the drying ovens. The core is really held together by a very thinly distributed paint, as it were. Hence also the great number and high percent- COREMAKING ages of drying adulterants used to "improve" a binder which would be most excellent if furnished pure. The solutions of gums and resins in petroleum, the asphaltic base residues of crude oil, and many other oils having a mixed mineral and vegetable origin come within this group. Selection of Binder The choice between liquid and dry binders lies in the nature of the core to be made. As previously stated, the liquid binders have a strong tendency to migrate to the surface. The thicker the core the more time necessary to bake it properly; and therefore the greater the quantity of binder collected at the skin of the core. The consequence is, that with heavy cores the situation may become so serious that not only will the molten iron flow over a surface as dense and impenetrable as stone, but in the charring of the binder considerable gas is formed which can only escape backward by "blowing" into the iron. The result is always a lost casting. On the other hand, with very thin cores, the oxidation of the oil is more rapid and thorough and migration of the oil is retarded. Liquid binders are therefore applied to very light section cores, whether these be large or small. Or, if used for heavier work, molding sand is added to help retard the oil migration mentioned. Dry binders, on the other hand, particularly if mixed with the sand as previously described, remain evenly distributed in the mass of the core and hence make it equally strong as well as permeable to air and gases throughout. The cus- tomary practice of using more dry binder than would be the case with the liquid varieties is readily shown to be illusive if the mixing is done properly. The binder after softening up all night on reworking in the morning is spread very thinly between the sand grains, and hence much less binder will give satisfactory results than where the mixture is used directly after putting the ingredients together. Indeed, the foundryman who avoids this extra labor simply damages his pocket in the long run by using an excessive quantity of binder or else losing castings. Further, by employing proper mixing machines he will get better metal surfaces and please his cus- tomers, besides saving on the binder used. Attention should be called to the mistake often made in mixing oil and paste binders. The latter are baked properly at about 350 degrees F., whereas linseed oil requires about 450. Either the full value of the oil will not have been obtained when baking for the paste binder, or the latter will be ruined if baking for the oil. 10 COREMAKING It will not be necessary to go into the details of core- making, such as filling the interior of large structures with coke, and making use of wax vent wires or tapers, the details of rodding and the use of arbors, grids, dryers for baking delicate cores, etc. Nor will the pasting of cores and slurry- ing the joints need special attention here, as foundry men are entirely familiar with these things, and if they know their business will give mighty close attention to them. What the average foundryman, however, needs badly and has little time or practice in working out, is a series of comparable tests on core binders based upon some unit of performance known to the trade generally. With this he can make his own test of the binder he contemplates purchasing, or is get- ting from time to time, and can figure out the relative econ- omy. Thus, if he has to pay a certain price for linseed oil, and can get equal strength and better results with another binder for less money, he would certainly be asleep if he did not take advantage of the situation. It is a mistake to keep on using a material that can be replaced by a more economical product if the latter gives equal or even better service. In the development of civilization there is room for everything and a material replaced in one industry finds its application in another, and probably to better advantage. The producer is not only constantly at work improving his product — otherwise his business dies of dry-rot — but he is also searching the world for new markets. The foundryman who does not do the same, will fall behind in the race. Core Tests To aid the foundryman in valuing core binders, a series of tests has been undertaken with characteristic representa- tives of the various classes of core binders discussed. To note the binding effect on the sand, two lines were followed. First, using an all silica sand — in this case "sea sand" was selected; and second, a mixture of this sea sand three parts, with one part of "Lumberton" molding sand. The molding sand was of medium grade of fineness. The all-silica sand grpup would correspond to the smaller range of cores, and the molding sand mixture to the heavier lines. The proportions of binder used were the following: One binder to fifteen sand, to illustrate the use of excessive quan- tities of binder. Next, one binder to twenty-five sand, to correspond with ordinary practice requiring fairly good strengths. Then, one binder to fifty sand, which would be called quite economical. Finally, one binder to one hundred sand, as an example of extreme economy and, unless great 11 COREMAKING care is used, rather beyond the Ime of safe practice. Indeed, when using linseed oil in this proportion it was impossible to get the cores to hold their shape when first made in the case of the molding sand mixture until this had first been tem- pered with water. The extremely small quantity of oil was absorbed by the clay content and prevented from exerting any adhesive action. Even in the case of the sea-sand, or all- silica material, the mixture had to remain unused for a while to allow the oxidation of the oil to begin. The cores could then be made and gave good results in spite of the minute quantity of oil used. Since all the binders other than linseed oil (and even this for the molding sand mixture) were used in connection with sufficient water to properly temper the sand, no trouble was experienced in making the cores in the usual manner of the shop. The core mixtures were all allowed to stand a while before using to aid in the attainment of uniformity of moisture and the proper softening of the dry binders. After drying and baking in an electric drying oven, the upper and rear portion of which was kept at the maximum temperature given in the tables, and the lower part above 225 degrees F. — the core plates full of cores being shifted from the bottom upward during the process of baking — the cores made were subjected to a transverse breaking test. The cores were all 1 inch square and seven inches long. When placed on supports six inches apart and the load applied cen- trally, the figures given in the tables to follow were obtained. The temperatures may be taken as approximate only, but are near enough to be correct for practical purposes. The strength is given in pounds, and as a whole the tables show some very interesting figures. The binders used were "Hydrol," Molasses, Waste Sulphite, Liquor Concentrates, for the liquid binders. "Kordek," a dextrine and starch product made from com, and Flour (wheat) represented the paste binders. Rosin (used with equal parts of flour) was selected as a type for the gums. Linseed oil, representing the oils, completed the list. It may be stated that the linseed oil used was absolutely pure and obtained from the original producer. In the case of the rosin and flour cores, the binder proportions refer to half flour and half rosin in each case. Thus, for one part binder to fifty sand, this means one-half flour and one-half rosin to fifty sand. The tables of results now follow: 12 COREMAKING Linseed Oil Transverse strength of 1* square Cores broken on supports 6* apart All Core Sand Core Sand 3, Molding Sand 1 Approximate Temperature Binder and Sand Proportions Binder and Sand Mixture Proportions , Degrees F. 1 : 15 1 :25 1 :50 1 : 100 1 : 15 1 : 25 1 :50 1 : 100 lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. 275 13.73 9.21 4.44 3.45 17.75 13.26 10.30 4.12 300 15.11 11.90 7.79 3.99 17.36 14.19 10.80 4.14 325 15.18 12.61 11.55 4.81 22.79 16.04 13.73 5.06 350 16.50 15.18 13.97 4.77 30.95 17.62 17.58 5.52 375 19.89 22.70 20.83 8.45 35.05 30.21 23.54 9.77 400 48.00 32.27 22.33 9.02 48.62 32.67 26.49 11.80 425 55.39 36.19 36.93 10.82 72.93 54.98 36.10 12.53 450 78.94 49.99 40,42 11.07 84.92 60.43 44.97 12.68 475 45.63 36.74 25.26 5.98 47.26 35.44 37.73 4.80 **Kordek" Transverse strength of 1" square Cores broken on supports 6" apart. Approximate Temperature Degrees F. All Core Sand Binder and Sand Proportions Core Sand 3, Molding Sand 1 Binder and Sand Mixture Proportions 1 : 15 1 :25 1 :50 1 : 100 1 :15 1 :25 1: 50 1 : 100 lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. 275 300 325 350 375 12.18 18.64 21.45 24.90 15.25 10.02 14.76 16.10 18.79 12.00 4.50 8.70 11.27 13.60 9.83 3.03 7.16 8.61 9.82 6.75 26.28 47.60 60.39 62.10 19.14 20.26 37.40 45.54 45.77 16.38 10.12 15.04 17.54 16.57 8.43 7.80 11.70 11.22 12.24 8.88 13 COREMAKING "Hydrol" Transverse strength of 1" square Cores broken on supports 6* apart. Approximate Temperature Degrees F. All Core Sand Binder and Sand Proportions Core Sand 3, Molding Sand 1 Binder and Sand Mixture Proportions 1 : 15 1 :25 1 : 50 1 : 100 1 : 15 1 :25 1 :50 1 : 100 lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. 275 300 325 350 375 22.60 41.82 55.44 66.78 57.08 14.47 17.36 40.94 47.20 44.81 8.44 16.08 21.77 25.40 22.10 7.22 10.70 18.14 20.53 15.62 38.15 54.78 62.28 66.42 59.11 20.67 25.08 27.45 33.66 28.80 9.33 10.41 15.90 16.86 14.70 6.43 7.00 8.60 10.22 9.14 Molasses Transverse strength of 1' square Cores broken on supports 6" apart. Approximate Temperature Degrees F. All Core Sand Binder and Sand Proportions Core Sand 3, Molding Sand 1 Binder and Sand Mixture Proportions 1 : 15 1 :25 1 :50 1 : 100 1 : 15 1 :25 1 :50 1 : 100 lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. 275 300 325 350 375 12.26 18.77 26.40 26.80 25.08 8.12 13.79 15.60 18.06 14.07 6.53 7.92 8.14 9.94 9.06 5.17 6.40 7.19 8.36 8.27 12.08 15.14 19.38 22.70 15.42 6.58 9.22 11.74 13.46 8.72 3.96 5.87 7.41 8.20 5.54 3.59 6.02 6.40 6.68 4.70 14 COREMAKING Waste Sulphite Liquor Concentrates Transverse strength of 1* square Cores broken on supports 6* apart. Approximate Temperature Degrees F. All Core Sand Binder and Sand Proportions Core Sand 3. Molding Sand 1 Binder and Sand Mixture Proportions 1 : 15 1 :25 1 :50 1 : 100 1 : 50 1 : 100 lbs. lbs. lbs. lbs. lbs. lbs. 275 300 325 350 375 2.10 2.58 3.47 3.81 2.90 1.32 1.75 2.80 3.17 2.05 0.76 1.13 1.87 2.19 1.41 0.24 0.98 1.20 1.52 0.65 8.20 13.80 14.52 14.80 13.14 3.02 5.44 7.81 8.33 6.65 Rosin and Flour Transverse strength of 1" square Cores broken on supports 6" apart. Approximate Temperature All Core Sand Core Sand 3, Molding Sand 1 Binder and Sand Proportions Binder and Sand Mixture Proportions Degrees F. 1 : 50 1 : 50 lbs. lbs. 275 300 325 350 16.68 23.76 24.08 21.16 7.41 16.84 17.50 17.18 15 COREMAKING Flour Transverse strength of 1" square Cores broken on supports 6' apart Approximate Temperature AH Core Sand Binder and Sand Proportions Core Sand 3, Molding Sand 1 Binder and Sand Mixture Proportions Degrees F. 1 :50 1 :S0 lbs. Ids. 275 300 325 350 12.77 16.20 19. SO 18.64 8.98 16.59 17.40 17.21 Discussion of Tests A study of the figures shows the following characteristics: That there is a best temperature for baking in each case. This temperature, however, can go up and down for some distance before the value of the cores are seriously impaired. For linseed oil 450 degrees F. shows the best strength, the higher ranges of heat beginning to destroy the binding prop- erty. This is as it should be, for a core is supposed to be gradually charred by the iron which has set about it in the process of pouring the mold. The dextrine binder ("Kordek") exhibited this property best of all, the carbonization being quite pronounced as the heat was run above the 400° point. The water-soluble binders gave the best results at 350 de- grees F., but were sufficiently strong from 300° to 375°. The proper pomt, however, would lie between 350° and 375°, for at the lower temperatures, in spite of showing good strength, the subsequent softening of the core by moisture absorption was found to be a decided detriment for storage purposes or retention in a mold over-night. In the case of a core with flour, the proper temperature ran lower, as 325 degrees F. shows up best. The dextrine binder ("Kordek") could be baked as high as the water-soluble binders safely, and of all the binders tried gave the least trouble from sraoke and gases ; in fact, these were hardly noticeable. The^ flour cores, and especially those with linseed oil, were a positive torture to every one near during the baking process. Before discussing the differences between the all-silica sand results and those from the sand mixture containing molding sand, it may be stated that the strength of the latter mix- ture (sea-sand 3 and molding sand 1) without a binder was obtained first. The material was tempered with water just 16 COREMAKING as in making a sand heap for molding purposes (7l4 per cent, water being the amount used) ; the cores dried in the oven, and then tested just as for the regular series. The average strength, on cross-breaking, of a number of these dry sand bars was 0.80 lbs. This amount represents the strength im- parted to the core by the clay content of the molding sand used, but evidently has nothing to do with the effect of the clay on the binders used in the regular tests, as the results show widely varying figures. In the case of linseed oil, "Kor- dek," and particularly the waste sulphite liquor, the strength of the cores made with molding sand in the mixture is higher than without it. The other binders, however, show exactly the reverse. This would indicate that mixing various types of binders must be watched, as the results may be poorer than if each binder had been used alone. Clay is a binder of the colloid type, and in these tests it has helped the strength in some cases and hurt it in others. Taking the binders individually, there will be noticed that linseed oil gives astonishingly fine results. This is because it happens to be the pure article, little of which finds its way into the foundry today. The linseed oil — sea sand, 1 : SO core, no molding sand and baked at 450° F. has been taken as the standard for comparison and called 1.00. The other binder results as related to this standard will be shown in a table further down. The "Kordek" results, while not as strong as those with linseed oil, are quite high, justifying the prevailing impression that dextrine is one of the best of binders known, tfnques- tionably this binder would show far higher results in com- parison with the "linseed oil" that gets into the foundries today. The results in the table show that the strengths are good from 300 degrees F. up. The higher ranges are safest for the moisture problem, hence where cores are to be stored — the general custom being to make up to 10 per cent, over the order — the darker ones should be selected for that purpose. "Hydrol" exhibits remarkable strength for a liquid binder, much of this being probably due to the general tendency of wet binders to draw to the surface. With rapid baking this tendency is counteracted somewhat, and when the higher safe temperatures are reached, the cores stand up excellently. "Hydrol" being a corn sugar molasses is destined to replace the regular cane sugar molasses to a great extent, as it becomes better known. A glance at the tables will show the reason. At the present moment, with the imminent prospect of the withdrawal of the country's entire supply of molasses for 17 COREMAKING munition purposes, it will pay foundrymen to try out this comparatively recent candidate for foundry favor. In the case of molasses, the difference between the two lines of sand is not serious. On looking at the waste sulphite liquor figures, however, one is astonished to see how poor they are for the sea-sand cores and how improved the results become when molding sand is added to the mixture. The rosin and fiour, as also the flour alone, show up good strength. These are old-time binders known to every foun- dryman. Rosin is now too expensive to find its way into the core room, and flour is only good when in first-class con- dition. The flour used in these tests did not consist of "sweepings," but is genuine wheat flour bought at the ordi- nary grocery. This accounts for the unusually high results obtained from flour, and flour and rosin, as compared with Kordek. At the present moment, the use of flour in the foundry is out of the question, both on account of food regu- lations and for patriotic reasons. The flour figures, therefore are of only secondary interest. The table above mentioned, showing the relative value ot the binders, the cores being taken at their best baking tem- peratures, and the comparison made with linseed oil- sand 1 ; 50, as above stated, now follows : Table Comparative value of Core Binders. Linseed Oil-Core Sand 1:50 (at 450° F.) equals 1.00 Baking Temper- ature Degrees All Core Sand Core Sand 3, Molding Sand 1 Binder Binder and Sand Proportions Binder and Sand Mixture Proportions F. 1 :15 1 :25 1 :50 1:100 1:15 1:25 1 :S0 1:100 Linseed OU. . Kordek Hydrol Molasses Sulphite Liq.. Rosin & Flour Flour 450 350 350 350 350 325 325 1.95 0.62 1.65 0.66 0.09 1.23 0.46 1.17 0.45 0.08 1.00 0.34 0.63 0.25 0.05 0.60 0.49 0.27 0.24 0.57 0.21 0.04 2.10 1.53 1.64 0.56 1.49 1.13 0.83 0.44 1.11 0.41 e.42 0.20 0.37 0.43 0.43 0.31 0.33 0.25 0.17 0.21 Discussion of Table of Comparative Values A few words are necessary in regard to the 1 : IS and 1 : 100 data. These are the exceptional cases in coremaking, the general run of work being found in a range from 1:2$ down to 1 ; 50 binder and sand. Nevertheless, in radiator 18 COREMAKING work or where cores must be readUy destroyed and shaken out in cleaning, the very dilute mixtures of strong binders find ready application. Foundries are not apt to buy flour in competition with bakeries, and rosin is too expensive. The smoke from flour after pouring is now subject to sanitary code regulations. Hence, in selecting a binder, the choice would be made from pure linseed oil, if obtainable at reasonable cost, Kordek, ^ hydrol and molasses, for cores made without molding sand; and the waste sulphite liquors in addition to the above list for cores made with molding sand. Taking into consideration the cost of pure linseed oil and the trouble from moisture ab- sorption on the part of the water-soluble binders, the dex- trine binder, Kordek, remains as best adapted for the gen- eral run of cores. For the practical range of binders (1:25 down to 1:50) pure linseed oil still holds the palm for strength, but after this it will be noted that Kordek and Hydrol give the best results for the dry and wet binders, respectively, both in straight sand and molding sand mixtures. This is easily understood when it is remembered that Kordek is essentially a dextrinized corn flour, while hydrol is a more highly concen- trated corn sugar molasses than the regular cane sugar mo- lasses of commerce. They bear out the statement previously made that modem developments run in the direction of eliminating the unessential portions of binders to save mate- rials, costs, and subsequent baking difficulties and annoyances. For weights and costs the following figures may be of value to the foundry man in comparing the dry and wet binders. The determinations were made on the actual materials used in the tests in question. Material Specific Gravity Weight per gallon in pounds Water.... Linseed Oil 1.000 0.934 1.258 1.263 1.401 8.34 7.79 Waste Sulphite Liquor Cone .... Molasses Hydrol 10.49 10.53 11 68 A final matter of interest may be given as the result of subjecting all the cores made to a microscopic examination. The structure of the cores of both sand mixtures was seen 19 COREMAKING to be extremely open — as it should be for proper venting. The grains of sand being rounded in a measure were forced into contact with each other at their flatter surfaces, and here the core binder cemented them together — a thin film for the poor mixtures and an "I" shaped cement like joint for the rich ones. It was further observed that for both wet and dry binders each grain of sand was coated with the binder all over its surface, showing that the bulk of the binder is wasted in coremaking. A further interesting observance was that the clay content of the molding sand used in the mixtures for half the tests evidently united with the binder by reason of the common vehicle — water — and separated from the sand grains suffi- ciently to form part of the cementing bond between them. This may explain why some binders gave stronger results with molding sand additions and others gave weaker ones. Some binders may have been absorbed by the clay to the detri- ment of their adhesiveness, whereas others may have been thickened by the clay addition and worked into points be- tween the sand grains rather than spreading evenly over them. The general impression resulting from the rather elaborate series of tests above described would seem to be that the core room presents problems far more serious than is generally sup- posed. In estimating on castings to be made the foundryman always considers the amount of core work first. If he had his core room equipped as it should be, his binders and mix- tures on a rational, economical and sound basis for strength, venting quality, etc., he would not have to worry so much about the costs for that particular end of his shop. The labor end is simple as compared with the molding floor, but the very ignorance of the fundamentals in coremaking has caused the core room to be the unreasonably expensive end of the foundry industry. 20 Tables 21 TABLES 1 4- oS lO 1/1 1/5 ^5 tSfO '8 •t/5 (1. ooo d So * gg^ o o g " d * §1 ooS o 9 o IS f^ fO f*> r<1 1*5 cu OOOOOOOO d SS^ ^-.-.?^^^ w * * * * >O00Ov0000u^OO OOOOO-;--© d ooS S§S§28S c ^gggicgiqg lO Oo ^sggggg cy5 88^ tC88^8i2g CM r^ ts — ^ 5 6 * ID oo»o>o»o 0. o % ? "? ^^^^^ C/D d 1 o oo oo2S§ 1 d so o ^.-. SS88S m 8^^ 8 -o5.^8 1 b z 1 T < 1 < c c c: t c 1 c < 1 c < c c X C 1 1 1 JX > > X , c • >. . a X C a. E E .a I 6 I s C 5 li 1 1 ) a 5x 2 X L L c .S t a \ ■■i il s II I to 22 TABLES > cs • 3.00 2.85 3.75 3.25 • -fO 00 Oi g : i^ . ^^^^ ? o •< ? : ;-. ^ W o \ 19 . ooS.2 o s ;< 1 : !-. o 1^ 8 : • o 88^8 8 . g 1 ? ; i? 8 W ©■ • :8 : ^8^^ - : ° ; ; ! '.XT) s 3 H •0000»r>0 -li • ITi O lO lO CN UO -f . ro f^ fO (^ fO fO -f OOOOOCO V) lO lO I/-, m O lO in ro <^ f^ tM fu -.-.^^ i °? jS^gS^S :? SOOOOOm 1< IT! \0 ^ 00 •* t^ w oqSS : oo ;S2g§§S :^ §§2S§§^. 1^ oooo • CO vOO"1 • oo 00 00 :g8SggS :g §8gg8g.i W 8^. • (M ri ^ -H ^ • ;???-.--. J3 13 •f5 IT) • t^ t^ 1/^ (~. «s 0. g : :g o • ggssg •OOOOO •M3 00 1O 0>/^ OT 9 : io o i O O O O O i^oooo c ? i ■o -. ; 8S^^g • oococ w :^ Castines o 1 i CQ ' K : £ : li 3^u '. a 1 S : 11 :^2 C 1 J, I Da ^ c :£(: If > O" ! si U ?2l 23 TABLES Weight of Cast Iron Variety Specific Lbs. per Gravity cu. ft. Coarse-grained gray pig iron Coarse-grained gray cast iron Fine-grained cast iron 6.80 7.00 7.20 7.64 7.69 7.80 7.10 7.50 6.79 7.50 7.07 7.68 7.06 7.52 7.15 7.53 7.06 7.52 425 437 449 Mottled pig iron 477 White pig iron 480 White, charcoal, high P. cast iron . . Average gray iron 487 443 Average white iron 468 Very open gra;^ coke pig iron This remelted in air furnace Cold-blast coke pig iron This remelted in air furnace Gray charcoal pig iron for malleable This remelted in air furnace Gray charcoal pig iron — sand cast. This iron — machine cast Gray interior of chilled roll Chilled portion near surface ... From Moldenke, "Principles of Iron Founding." Melting Points of Cast Iron, Brass, etc. Name Composition Melting Point Degrees F. Authority Brass CopF>er 95 Zinc 5 1,960 1,930 1,880 1,830 1,795 1,725 1,660 1,635 1,920 1,840 1.760 1,635 Shepherd « 90 "10 « 85 « 15 « « 80 ** 20 a « 75 "25 u « 70 "30 a « 65 "35 u « 60 "40 u Bronze Copper 95 Tin 5 Shepherd " 90 " 10 " 85 " 15 u " 80 "20 u 24 TABLES Melting Points of Cast Iron, Brass, etc. (Continued) Name Composition Melting Point Degrees F. Authority Cast Iron Averace erav 2,260 2,100 482 411 370 340 356 2,685 2,650 2,570 Moldenke « white « Solder Soft Tin 1 Le^d 3 Brannt « 1 « 2 M « 1 « 1 U « 2 " 1 U « 3 " 1 « Steel Low carbon Le Chatelier Medium carbon M High carbon (( From Various Sources. See also Fusible metals. Physics and Chemistry of Foundry metals, etc. Contraction Allowance for Various Metals and Alloys Name Contraction in Sixty-fourths Inch per Foot Ferrous Metals: — Steel 16 White Iron 16 to 12 Mottled Iron 9 Light Gray Iron 9 to 6 Medium Gray Iron 8 Malleable Cast Iron 8 Columns of Cast Iron 7 Cylinder and Engine Frames (large) Heavy Gray Iron 6 5 Non-Ferrous Metals and Alloys: Aluminum 14 Copper 14 ^ Brass 14 to 12 Bronze 12 ^ Zinc 12 Lead 12 Tin 10 Bismuth 5 From MoUUnbe, "Praaia o/ Iron Founding" (adf€uc4 sfuxts). 25 TABLES Estimating Weight of Castings from Pattern Material of Pattern Multiply Sp. Gr. of Weight of Material Pattern by 17.5 0.40 17.0 0.42 15.8 0.45 14.8 0.48 14.2 0.50 13.0 0.55 11.6 0.61 11.1 0.64 11.0 0.65 10.9 0.66 10.4 0.68 10.0 0.70 10.0 0.72 10.0 0.72 9.6 0.74 9.2 0.78 s.s 0.85 7.3 0.97 5.1 1.40 3.1 2.27 2.60 2.80 1.00 7.10 0.97 7.29 0.85 8.37 0.83 8.50 0.82 8.67 0.63 11.35 Cedar. Red Wood Poplar Cypress White Pine Birch Yellow Pine Ash Cherry Chestnut Maple Black Walnut Elm Beech Red Oak White Oak Hard Mahogany Hard Rubber Red Fibre Plaster Paris Aluminum (cast) . . . Zinc Tin Brass (yellow) , Copper Bronze (gun metal) , Lead From Moldenke, "Practice of Iron Founding" {advance sheets). 26 TABLES Cupola Melting Loss Material Per Cent. Loss Machine-cast Pig Iron 0.30 Sand-cast Pig Iron 1.00 Car Wheels 2.00 First Quality Machinery Scrap 2.50 Light Machinery Scrap 3 50 Stove Plate Scrap 8.00 From Moldenke, "Principles of Iron Founding.' Composition of Molding Sands Rational Analyses — ^Averages Region Quartz Clay Substance 58.82 18.99 64.53 24.77 71.02 23.79 64.10 24.36 67.21 21.99 81.38 15.49 70.82 16.65 77.37 17.94 74.53 21.11 65.53 21.73 Feldspar New York (Albany) , Kentucky Ohio.... Missouri Pennsylvania New Jersey Illinois Georgia Tennessee Grand Average 22.16 10.69 5.17 11.54 10.79 3.13 12.53 4.69 4.36 12.74 Recalculated for Ultimate Composition: Silica 84.26 Alumina (and Iron Oxide) 13.59 Lime, Alkalies, etc 2.15 From Moldenke, "Principles of Iron Founding." 27 TABLES Rational Melting Capacities of Cupolas Cupola Diameter, Tons melted Cu. ft. blast required inside lining (inchess) per hour per minute 18 0.5 250 24 1.5 750 30 3 1,500 36 4.5 2,250 42 6 3,000 48 8 4,000 54 10 5,000 60 13 6.500 66 16 8,000 72 19 9,500 78 22 11,000 84 26 13,000 90 30 15,000 Blast volume required to melt one ton of iron is taken at 30,000 cu. ft. To get speed of Positive Blower, divide the cu. ft. blast required per minute by the cu. ft. air of blower per revo- lution. From Moldenke, "Principles of Iron Founding." Composition of Various Alloys by Name Name l-r 1 ii 1 Other Metals Admiralty Metal . . Aich's Metal Ajax Metal Aluminum-copper Alloy 87.0 60.0 81.2 7.5 5.0 38.2 8.0 . 1.8 11.0 7.8 92.5 65.0 Aluminum-zinc Alloy 35.0 31.0 io.'o 20.0 34.0 27.0 10.2 33.3 40.0 Arguzoid Arsenic Bronze Bath Metal Bell Metal Bobierre's Metal.. . Bristol Brass Camelia Metal Cartridge Brass 48.5 82.2 80.0 80.0 66.0 72.8 70.2 66.7 60.0 60.0 Nickel 20.5 10.0 7.0 Arsenic 0.8 * ■ 4.3 0.2 14.8 0.5 Nickel 40.0 23 TABLES Composition of Various Alloys by Name (Continued) Name 1 1 Other Metals Cornish Bronze. . . . 77.8 65.0 76.8 57.5 64.0 3.3 76.0 5.0 7.0 71.9 60.0 50.0 75.8 88.0 64.5 55.7 94.0 12.5 10.0 57.0 "id.o ■46.0" 30.0 85.4 24.0 79.0 92.0 24.9 38.5 29.0 ■ '2.0 32.5 42.7 6.0 87.5 85.0 43.0 9.6 5.0 10.6 12.6 Damascus Bronze.. 12.6 Delta Metal 2.5 5.0 11.0 Nickel 1 .0 Die Casting Alloy.. 0.3 Dutch Alloy. ...... Fenton's Alloy 16.0 Fontaineinoreau's 1.0 French Brass (potin iaune) 1.2 2.0 Gedge's Metal 1.5 German Silver Nickel* ' 21.6 8.6 10.0 0.3 1.0 15.6 Gun Metal (U. S.). 2.7 Harrington Bronze . Jewelers' Gilding Alloy 0.6 Lap Allov 5.0 Macht's Yellow Metal 80.0 0.4 1.5 Manganese Bronze. Monel Metal 58.5 29.5 66.7 60.0 62.0 90.0 3.0 79.7 93.6 64.0 50.0 75.0 89.5 85.0 5.0 66.7 55.0 90.7 97.0 58.2 85.0 82.5 41.0 0.1 Manganese to deoxidize Nickel 69.0 Mosaic Gold 33.3 40.0 37.0 10.0 35.0 ' 6.'4' 30.0 Muntz's Metal. . . . Naval Brass 1.0 Oreide (French Gold) Parson's White Brass 62.0 10.0 9.5 Phosphorus 0.8 Pinchbeck Plastic Bronze 5.0 Nickel 1 .6 50.0 Prince's Metal 25.0 10.3 10.0 90.0 42.3 8.3 2.0 39.5 15.0 17.5 Red Metal 5.0 0.2 Similor (Mannheim Gold) Sorrel's Alloy 5.0 Speculum Metal . . . 33.3 0.9 Sterro Metal 1.8 Talmi Gold Gold 1 .0 Tissier's Metal Arsenic 1 .0 Tobin Bronze 2.3 Tombac Toumay's Alloy... . From various sources. Alloys, etc. See also tables of Antimony Alloys, Fusible 29 TABLES Composition of Various Brasses by Color Color Bluish gray Ash gray Silver white Pale yellow Yellow Red yellow Yellow red Orange Zinc From various sources. Brass Solders Copper Zinc Tin Lead Color Properties 58 42 .. Red Yellow Very strong 53 47 u u Strong 50 50 u u Medium 33 67 White Easily Fusible 44 50 4 2 Gray 57 28 15 White White Solder From Iliorn's "Mixed Metals. Fusible Alloys Name Melting Point Tin Bis- muth Lead Cad- mium Fusible Alloy Lipowitz's Alloy . . . Wood's Alloy Fusible Alloy Onion's Alloy Newton's Alloy Clichet Alloy Rose's Alloy 150° F. 158°F. 160° F. 187° F. 197° F. 202° F. 221°F. 230° F. 1 4 2 4 2 3 2 1 4 15 5 "s 8 5 2 2 8 4 2 3 5 2 1 1 3 2 2 From Hiom's "Mixed Metals. 30 TABLES Antimony Alloys Name 1 < 5 G a N 1 1 s G PQ .a 2: Tvpe Metal 30.0 25.0 18.4 18.2 16.0 16.0 16.0 14.0 12.1 11.8 11.7 10.0 9.3 8.3 8.0 7.1 7.0 4.0 60.0 80.0 '79.0 76.0 79.0 87.9 83.7 88.3 ■83."4" ■92.0 10.0 25.0 68.5 5.0 8.0 5.0 80.0 Tutania Metal American Anti-friction Metal 9.0 1.0 10.0 16.0 ' *3.3 0.6 25.0 Minofor Metal Linotype Metal Monotype Metal Magnolia Metal Ashberry Metal 1.0 2.0 3.0 White Metal Stereotype Metal Anti-friction Metal 4.0 0.5 Algiers Metal 90.0 81.5 8.3 81.5 88.5 90.0 4.0 Hard Babbitt Metal. . . 9.2 Metallic Packing Genuine Soft Babbitt Metal ' 0.9 4.0 3.5 3.0 Queen's Metal ■ * * * * Britania Metal Electrotype Metal From various sources. 31 TABLES Copper-Tin Alloys ob Cop- Tin per 100 8.921 49 8.564 25 8.649 13 8.694 10 9 8.669 8 8.353 7 8.648 6 5 8.462 4 .... 3 8.870 7 8.932 ?. 8.907 3 1 8.539 8.790 4 8.300 2 8.132 1 7.835 1 7a543 1 7.490 t 10 7.472 1 12 7.417 1 89 7.305 100 7.293 Color Tensile Strength Lbs. per sq.in. Authority Use Red Reddish yellow u u Grayish yellow u n a u Yellowish red Reddish white 32,000 28,500 32,093 26,860 26,011 31.100 44,071 34,048 35,739 White Dark gray Bluish white Grayish white 5,585 2,536 1,120 ' 2.820 6,775 3,798 6,450 6,096 3.650 3,500 Marchand Thurston Muschenbroek Thurston Wade Thurston Muschenbroek Mallet Muschenbroek Riche Thurston « Mallet Wade Riche Thurston Tomson Wade Thurston Cast copper Ordnance Gun Metal Brittle Mirrors Bell Metal Condensed from Hiorn's "Mixed Metals.' 32 TABLES Copper-Zinc Alloys Cop- per Zinc Speci- fic Grav- ity Color Tensile Strengh lbs. per sq. in. Authority Use 10 9 8 1 1 1 1 1 1 1 1 1 2 1 3 5 2 9 5 11 3 4 5 8 8.605 8.607 8.633 8.587 8.710 8.673 8.650 8.379 8.392 8.363 8.291 8.171 7.974 7.859 7.811 7.766 7.882 7.449 7.371 7.136 7.108 Red yellow « a u u u it u « Yellow red Yellow Silver white « « « « Ash gray « ^ mile =201.17 meters. Gallon =231 cu. in. =3.78543 liters =3,785.43 cu. centimeters. Gill=}i pint. Grain =0.0648 grammes =64.8 milligrammes. ■Gramme = \5Ai grains. Hogshead =63 gallons =2 barrels (31.5 gallons capacity) =238.48 Liters. Inch = 2.54: centimeters =25.4 millimeters. Karat =200 milligrammes =0.2 grammes =3.0865 grains. Kilogramme = 1 ,000 grammes =2.20462 pounds avd. JiCitowe^cr = 1,000 meters =3,280.83 ft. =0.62137 miles. Knot (Nautical or geographical mile) =6,080.2 ft. = 1.15155 miles = 1.85325 kilometers = 1 minute of earth's circumference. League = 15,840 ft. =3 miles =4.828 kilometers. J^ink =one hundredth of measuring chain = 12 in. (Engineer's chain) = 7.92 in. (Surveyor's chain) =20 centimeters (Metric chain). Liter = 1,000 cu. centimeters =61.023 cu. in. =0.0353 cu. ft. =2.1134 liquid pints = 0.2642 gallons. Meter =39.37 inches =3.28 ft. Mile =5,2SO ft. =1,760 yards. A square mile equals 640 acres =2.59 sq. kilometers. Milligram =0.001 grammes =0.015432 grains. Millimeter =0.001 meters =0.03937 inches. Ounce, Apothecary. Same as troy ounce =480 grains =31.104 grammes. Avoirdupois =437.5 grains =28.35 grammes =0.9115 ounce troy or apothecary. Troy (for gold and silver) =480 grains =20 pennyweight = 31.104 grammes = 1.097 ounces avd. Peck =0.25 bushels =8.81 liters. Pennyweight =24 grains = 1.555 grammes. Pint, Liquid =0.125 gallons =0.4732 Hters. Dry =0.5 quarts =0.55061iters. Pipe or Butt = 126 gallons =2 hogsheads =476.96 liters. Pounds, Avoirdupois = 7 ,000 grains = 16 ounces (avd.) =0.4536 kilogram- mes. Troy or Apothecary =5,760 grains = 12 ounces =0.3732 kilo- grammes. Quart, Liquid =0.25 gallons =0.94634 liters. Dry =0.03125 bushels =67.2 cu. in. =1.1 liters. Rod or Perch or Pole = 16.5 ft. =5.5 yards =5.0292 meters. Rood =0.25 acres =40 sq. rods = 1,210 sq. yds. =1,011.72 sq. meters. Scruple =20 grains = 1 .296 grammes. Section of land = 1 mile square =640 acres. Stone = 14 pounds (avd.) =6.35 kilogrammes. Ton (gross) Displacement of water =35.88 cu. ft. =1,016 cu. meters, (gross or long) =2,240 lbs. (avd.) =1.12 short or net tons = 1,016.05 kilogrammes = 1.01605 metric tons, (netorshort) =2,000 lbs. (avd.) = 20 hundredweight =907,185 kilogrammes =0,907185 metric tons = 0.892857 long tons, (metric) =2,204.62 pounds (avd.) =1.10231 net tons =0.9842 long tons = 1,000 kilogrammes. Cubic yard =27 cu. ft. =46,656 cu. in. =0.76456 cu. meters. Square yard =9 sq. ft. =1,296 sq. in. =0.836 sq. meters. Yard =3 feet =36 inches =0.9144 meters. From Lefax Data Sheet.^, 42 TABLES Temperature Conversion Formulae To change from Fahrenheit scale to Centigrade: Subtract 32, multiply remainder by 5 and divide by 9; (F° —32) 5 -^9 = C^ Centigrade to Fahrenheit: Multiply by 9, divide product by 5, add 32 to quotient; (C X 9 -^ 5) + 32 = F^ Fahrenheit to Reaumur: Subtract 32, multiply remainder by 4 and divide by 9; (F** _ 32) 4 -H 9 = R°. Riaumur to Fahrenheit: Multiply by 9, divide product by 4, add 32 to quotient: (R° X 9 -i- 4) + 32 = F^ Weight of Gases Name Symbol Specific Gravity Lbs. per Cu. Ft. Cu. Ft. per Lb. Air O N H NO N20 CO C02 so 2 NH» C2H2 CU* cm* 1.000 1.105 0.970 0.0696 1.038 1.522 0.968 1.520 2.213 0.590 0.899 0.554 0.520 0.969 0.0807 0.0892 0.0783 0.00562 0.0838 0.1229 0.0780 0.1227 0.1786 0.0476 0.0725 0.0447 0.0394 0.0780 12.387 Oxygen 11 204 12.753 Hydrogen 178.830 Nitric Oxide 11.933 Nitrous Oxide 8.14& Carbon Monoxide Carbon Dioxide 12.804 8.101 Sulphur Dioxide . . 5 590 21.020 Acetylene 13.793 Methane 22.350 Natural Gas 25.140 Ethylene 12.580 From various sources. 43 TABLES Metric Conversion Table Millimeters X 0.03937 = Inches. Millimeters -r 25.4 = Inches. Centimeters X 0.3937 = Inches. Centimeters -r 2.54 = Inches. Meters X 39.37 = Inches. Meters X 3.281 = Feet. Meters X 1.094 = Yards. Kilometers X 0.621 = Miles. Kilometers -r 1.6093 == Miles. Square Millimeters X 0.00155 = Sq. Inches. Square Millimeters -j- 645.1 = Sq. Inches. Square Centimeters" X 0.155 = Sq. Inches. Squzire Centimeters -r- 6.451 = Sq. Inches. Square Meters X 10.764 => Sq. Feet. Square Kilometers X 247.1 = Acres. Hectare X 2.471 = Acres. Cubic Centimeters -r- 16.383 = Cu. Inches. Cubic Meters X 35.315 = Cu. Feet. Cubic Meters X 1.308 = Cu. Yards Cubic Meters X 264.2 = Gallons (231 cu. in.). Liters X 61.022 = Cu. Inches. Liters X 0.2642 = Gallons. Liters -r- 3.785 = Gallons. Liters -r- 28.316 - Cu. Feet. Hectoliters X 3.531 = Cu. Feet. Hectoliters X 2.84 = Bushels (2,150.42 cu. in.). Hectoliters X 0.131 = Cu. Yards. Hectoliters -r 26.42 = Gallons. Grammes X 15.432 = Grains. Grammes -r- 28.35 = Ounces Adv. Grammes per Cu. Cent, -r 27.7 = Lbs. per Cu. In. Kilogrammes X 2.2046 = Pounds. Kilogrammes X 35.3 = Ounces Adv. Kilogrammes -r 907.2 = Tons (2,000 Lbs.). Kilogr. per Sq. Cent. X 14.223 = Lbs. per Sq. In. Kilogramme-meters X 7.233 = Foot-pounds. Kilogramme per Meter X 0.672 = Pounds per Foot. Kilogramme per Cu. Meter X 0.062 = Pounds per Cu. Ft. Kilowatt X 1 .34 = Horse Power. Watts -r 746 = Horse Power. Watts X 0.7373 = Foot Pounds per Second. Calorie X 3.968 = British Thermal Unit. Cheval Vapeur X 0.9863 = Horse Power. From Arrangement byC. W. Hunt, New York. 44 Index 45 Index Page Alloys and metals, contraction allowances for various 2S Moys, antimony 31 Alloys, composition of various, by name 28' Alloys, fusible 30 Alloys, tin-copper 32 Alloys, zinc-copper 33 American Foundrymen's Association. Scrap specifications. 35 Amer. Soc. for Testing Materials. Preparation of samples for analysis 3& A.mer. Soc. for Testing Materials. Standard specifications for gray iron castings 41 Analyses for various classes of castings, recommended 22 Analyses of molding sands, average 27 Analysis, preparation of samples for 38' Antimony alloys 3L Binders, characteristics of core 7 Binders, classification of core 6 Binders, comparative value of core 18 Binders, core 4, 6, 9 Binders, paste 8 Binders, selection of core 10 Binders, various kinds of 6 Brasses, composition of various, by color 30 Brasses, melting points of 24 Brass solders 30 Bronzes, melting points of 24 Castings, elements entering into making good 3 Castings, estimating weight of, from patterns 26 Castings, recommended analyses for various classes of 22 Castings, standard specifications for gray iron 41 Cast iron construction, factors of safety in 38 Cast iron, melting points of 25 Cast iron, sampling 39 Cast iron, scrap specifications 35 Cast iron, weight of 24 Chemical and physical data of foundry metals 34 Coke, sampling 39 Color, composition of various brasses by 30 Combustion data for gases 33 Comparative value of core binders, table of 18 INDEX Converter steel scrap specifications 38 Contraction allowances for various metals and alloys 25 Copper-tin alloys 32 Copper-zinc alloys 33 Core binders 4, 6, 9 Core binders, characteristics of 7 Core binders, classification of 6 Core binders, selection of 10 Core binders, table of comparative value of 18 Core, definition of 3 Coremaking 3 Core requirements 6 Core sand, characteristics of 4 Cores, softening of 7 Core tests, comparative 11 Core tests, discussion of comparative 16 Cupola melting loss 27 Cupola melting capacities 28 Estimating weight of castings from patterns 26 Plame temperatures 34 Flour core tests 16 Foundry metals, physical and chemical data of 34 Factors of safety in cast iron construction 38 Fusible alloys 30 Gases, combustion data for 33 Gases, weight of 43 Gray iron castmgs, standard specifications for 41 Gray iron scrap specifications 35 Hydrol core tests 14 Hydrol, weight of 19 Kordek core tests 13 Linseed oil core tests 13 Linseed oil, weight of 19 Malleable cast iron scrap specifications 36 Measure, units of 42 Melting capacities of cupolas 28 Melting loss in cupolas 27 Melting points of cast iron, brass, etc 24 INDEX Page Metals and alloys, contraction allowances for various 25 Metals, physical and chemical data of foundry 34 Metric conversion table 44 Molasses core tests 14 Molasses, weight of 19 Moldenke, Dr. R. : Coremaking 3 Mold, action of molten metal on 4 Molding sands, average composition of 27 Open hearth steel scrap specifications 37 Patterns, estimating weight of castings from 26 Physical and chemical data of foundry metals 34 Pig iron, sampling 39 Rosin and flour core tests 15 Samples for analysis, preparation of 38 Sand characteristics, for cores 4, 5 Sands, molding, average composition of 27 Scrap specifications of American Foundrymen's Association 35 Solders, brass 30 Solders, melting points of 25 Specifications for gray iron castings, standard 41 Specifications for scrap, of American Foundrymen's As- sociation 35 Specific gravity of cast iron 24 Steel, melting points of 25 Steel scrap specifications, converter 38 Steel scrap specifications, open hearth 37 Sulphite liquor core tests. 15 Sulphite liquor, weight of 19 Temperature conversion formulae 43 Temperatures, flame 34 Tests, comparative core 11 Tests, discussion of comparative core 16 Tin-copper alloys 32 Units of measure 42 Weight of cast iron 24 Weight of gases 43 Zinc-copper alloys 33 o X H