Patent ID: 7237375

Claim:
A method for investment casting chain links comprising the steps of: a) providing a metal die having a cavity defining a chain link formed therein; b) injecting wax into the chain link cavity of the metal die to form a wax pattern having a pair of hollow cores that form pin bores in the chain link to be cast; c) assembling a plurality of wax patterns on a feeder system; d) sequentially forming an investment on each wax pattern on the feeder system at least three times; e) masking the hollow cores with a combustible heat dispersing element to prevent further investment build up on inside surfaces of the hollow cores; f) further sequentially forming investment on each wax pattern to form a ceramic shell around each wax pattern; g) placing the ceramic-coated wax patterns in a steam chamber to melt and eliminate the wax and form ceramic molds; h) heating and curing the ceramic molds in an oven while burning away and removing the heat dispersing elements from the hollow cores; i) pouring molten stainless steel alloy into the heated and cured ceramic molds; j) cooling the ceramic molds to solidify the stainless steel alloy therein; k) breaking away the ceramic molds to leave a series of castings defining stainless steel chain links; and l) cutting, grinding and finishing the castings to form completed chain links.