^•TA May I9U3 BT-209 United States Department of Apiculture Agricultural Rese3/4" long, cut to the shajM shown In figure 1. The end holding the crank pin was left a full inch in thickness. One and one-half inches in from this end a saw out 3/^" ^^^V ^^* ""^^^ «u3d a piece of that thick- ness was split out, learing the remainder of the block 3/8" in thicks ness to proTide clearance for the connecting rods. The eccentrics were fastened to the feu:e plates "by three l/k* flat-headed stove bolts l-l/^" long, countersunk in the wood. Connecting rods of hard, straight-grained gum wood were made S-l/U** long and 3/^" square. One end of each rod was fastened to the oak eccentric bj means of a crank pin made of a ^/iS" machine bolt 2-1/8" long, threaded to within 1" of the head. The pins were screwed into holes bored in the eccentrios 2-1/4" out from the cen- ter of the face plates. At the other end the connecting rods were attached to the frame holding the screen b7 meant of 1" hinges. With the light loads handled, the wooden connecting-rod bear- ings gare no trouble from heating or wear. The wood was hard, and the bearings were kept oiled. Ball bearings ajod more durable crank pins would be, preferable where more serere conditions are to be met. A frame from which to suspend the moving screen was made with four legs 29" high of 1" x U" white pine stock, tapered to a width of 2-1/2" at the bottom. At the corners on the side opposite the operator, where room for removing the screen was not needed, two of the legs were doubled, with the members at right angles to one an- other. At the top the legs were screwed to a frame 21-3/4" z 27-1/2", using 10-gauge screws 1-1/2" long. The legs were secured to the supporting stand by iron angles. ?or added rigidity, the cross mem- bers of the top frame were set in from the ends of the side members a distance of H-3/4" and were braced with triangular wooden corner pieces. A black iron baking or drip pan with the bottom replaced by a wire cloth of 6 meshes per inch, leaving a narrow edge all around, was used for the screen. A wire-cloth lid, hinged near the middle, prevented the raisins from being thrown out. This screen, I7-7/8" z 19" by 2-I/2" deep, was removably set in a wooden frame of 1" z U" white pine built to hold it snugly. The frame was suspended by four strips of oiled oak, 1-1/2" z I/8" and I7-I/2" long. They were each fastened rigidly at the top with four round-headed screws, two of which passed first through a metal plate 1" z 1-1/2" by I/8" thick to reinforce the attachment of the oak hangers. The lower ends of the strips were fastened to the screen frame by 1" hinges which were atteiched to the strips by ^/S" stove bolts passed through a metal plate 1-1/2" X 1", for added strength. The other leaves of the hinges were screwed to the screen frame. - 3 - Beneath the screen, a while enamel developing i>an, 20" x SM-", was used to catch the alftings, the pan being raised on guides to hold It near the bottom of the screen. Referring to the Illustra- tion, there was room for the removal of the screen to the -right, while the pan was withdrawn on the side opposite the motor. A switch between the motor and a wall plug was provided for convenient start- ing and stopping. The cost of the sifter, not Including labor or the cost of the stand, was about as follows: Lumber, $3*00; shaft, bearings col- lars, pulleys, face plates, and belt, $7*76: miscellaneous hardware, $2.29; trash pan, $1^.17; motor, $S,^i total $23.67. ,»^^m»-^^^^m-^-,-^. Figure l.-Fast-aotion sifting machine mounted on heavy stand. UNIVERSITY OF FLORIDA 3 1262 09240 8813