The pattern maker's assistant : embracing lathe work, branch work, core work, sweep work, and practical gear construction : the preparation and use of tools : together with a large collection of useful and valuable tables (1878)
Rose, Joshua · New York : D. Van Nostrand · leaf 97
90 PATTERN maker's ASSISTANT. piece be molded tlie reverse way to that shown in Fig. 88— that is to say, it must be molded as shown in Fig-. 90 — with the flange downwards; for it may be here noted that the soundest part of a casting is always that at the bottom of the mold; and furthermore^ the… … is more dense, heavier, and stronger than it is at the top, for the reason that the air or gas, which does not escape from the mold, leaves holes in the top of the casting, or as near to the top as it can — by reason of the shape of the casting — rise. The bottom metal also has the weight of the…
Patternmaking
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
