The manual training school, comprising a full statement of its aims, methods, and results, with figured drawings of shop exercises in woods and metals . mold-boari Fig. 112. LowEu Half of Pattern in Drag. Now comes the second step. The whole is carefully turnedover and the mold-board is laid aside. The upper part of thepattern is now laid in place, guided by the little pins, and thecope is put on, guided^by its plates, over the pins on the thin layer of parting-sand is dusted over the whole. Arunner plug which molds a passage for pouring is set up nearthe pattern, and the sand is filled
The manual training school, comprising a full statement of its aims, methods, and results, with figured drawings of shop exercises in woods and metals . mold-boari Fig. 112. LowEu Half of Pattern in Drag. Now comes the second step. The whole is carefully turnedover and the mold-board is laid aside. The upper part of thepattern is now laid in place, guided by the little pins, and thecope is put on, guided^by its plates, over the pins on the thin layer of parting-sand is dusted over the whole. Arunner plug which molds a passage for pouring is set up nearthe pattern, and the sand is filled in and rammed, a riser plug. Fig. 113. Patterns in Position in the Sand. being put on the highest part of the pattern but not on thecore-print. When the packing is finished, the appearance willbe as in Fig. 113, which shows step No. 2 completed, a is therunner, and b is the riser. 116 THE SECOND, on MIDDLE YEAR. [ch?,p. IIL The runner and riser are now drawn out; the coj)e is gently-lifted off, turned over, and laid on the mold-board. A draw-spike is driven into the pattern in the drag, and the pattern isloosened by gentle raps on the spike as it is held by the lefthand. The pattern is then lifted out of the mold, technicallydrmvn, by the spike. A gate is now cut from the lower endof the runner to the mold, using a gate-cutter (Fig. 109). Thepattern in the cope is now treated in the same way, anddrawn. The cores are next placed in the mold, and the copebeing replaced the liquid is poured in, filling the mold as inFig. 111. If molds are poured with plaster it will be found necessaryto have the runners, gates, and
Size: 1728px × 1446px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectmanualt, bookyear1906
