shrinkage will of themselvescrack the casting at this point and at all similar sharpinternal angles. If the above casting is made with afillet or rounded-in angle, this is not so likely to be thecase, and if it is made as represented by Fig. 5 it will bejust as strong at that point as at any other.… … There is another advantage gained in thus roundingin these internal angles that is appreciated by the molder.In molding a pattern of the general shape of Fig. 7(a), thatfor some reason has to be pulled or drawn from the moldin the direction of the arrow, a very sharp corner of sand 32 WOOD PATTERN…
Patternmaking
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