A machine I am working on has a broken pot-metal knob that needs to be
re-cast.  I have one good knob that can be used as a pattern.

Can I cast a replacement myself by making a two piece mold and using
some sort of white metal?  If so, where do I find the white metal and
the mold material for this job?

What sort of mold material do I need to use for this re-casting, plas-
ter, plastic, or what?  Do I need to make a rubber mold of the good
part first, then use this for making the actual casting mold, with
vents, etc.?

Has any MMDer ever done metal casting?  Or can you recommend someone
with casting experience to do the job for me?

Brad Hunter
near Philadelphia