Pattern making and foundry practice; a plain statement of the methods of wood pattern making, as practiced in modern pattern shops, with complete instructions for sweep work and notes on foundry practice, together with numerous drawings taken from actual patterns .. . itili itoseci cAist? The parting tool, Fig. 20, is used for cuttingdeep grooves and for cutting off work in thelathe. The diamond point. Fig. 21, and the 52 PATTERN MAKING bull-nosed chisel. Fig. 22, are used for turningboth the outside and inside surfaces of hollowpatterns, such as the piece shown in cross-sectionin Fig. 23. Fig
Pattern making and foundry practice; a plain statement of the methods of wood pattern making, as practiced in modern pattern shops, with complete instructions for sweep work and notes on foundry practice, together with numerous drawings taken from actual patterns .. . itili itoseci cAist? The parting tool, Fig. 20, is used for cuttingdeep grooves and for cutting off work in thelathe. The diamond point. Fig. 21, and the 52 PATTERN MAKING bull-nosed chisel. Fig. 22, are used for turningboth the outside and inside surfaces of hollowpatterns, such as the piece shown in cross-sectionin Fig. 23. Figs. 15, 16 and 17 can be procured at hard-. Ti^ 23 ware stores generally. The rest can be had fromlarge supply houses, or from dealers in toolspecialties, or they can be made by a first-classsmith. In addition to the tools heretofore men-tioned, the pattern maker will sometimes find it AND FOUNDRY PRACTICE 53 convenient to have special tools of a peculiardesign for some special work. The shrinkage rule is a measure designedespecially for pattern making, and is intended tomake the proper allowance for the contractionof metal in cooling. However, it is not possibleto accurately figure the contraction or shrinkageof metal, as a thick casting will shrink morethan a thin one. Some shapes shrink more thanothers or more in some parts of the same piecethan in other parts. A large cylinder, if cast onend, will shrink more at the bottom than at thetop. Castings are calculated to shrink from one-tenth to one-eighth of an inch to the foot; but,as nearly all machine castings are either turnedor planed to an accurate size, the determina-tion
Size: 1615px × 1547px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublisherchicagofjdrakeco
