Mike
When Bob had it casted do you have to have one that is mint to cast from or can they fix it in the mold before they pour the new one?
Bob had a pattern made. Because of the shrinkage of steel when you pour it. A pattern has to be made 1/4 inch bigger per foot to allow for skrinkage. Mike
When a pattern maker makes a pattern he uses what is called a "shrink rule" or some places called a "pattern makers ruler" that still reads like a normal rule but has been scaled for this shrinkage for the particular material being cast. As stated steel is 1/4" per foot cast iron is 1/8" per foot.
http://www.freemansupply.com/StarrettSteelShrin.htm
That's some fine workmanship Bob. Are they going to be cast steel? Is the machine shop going to machine the sprocket teeth and heat treat the teeth also?
If you cast the best 2speed sprocket I want a set .
Ron Meeder best no. 1624
Hey Bob, Sent you a PM note regarding the sprockets. Greg