Back to Ganoksin | FAQ | Contact

Metal shrinkage during casting

I’ve done my first six 3D models to be sent to a prototyping machine.
I’m much better on the computer than in wax :-).

I’m aiming for a ring of 15.25mm inside diameter. Normally, when I
work in wax, I do the “make it a half size big” thing. That would be
16.08mm, or 5.4% larger.

I read that gold shrinks 1 to 1.5% though… I’m supposing that the
additional difference is going to come out of filing and polishing.

Right now my 3D models are all in exact scale. I need to scale them
up before casting… does anyone know what shrinkage amount I should
expect when casting:

	(1) sterling silver
	(2) 22kt gold
	(3) 18kt gold
	(4) 18kt white gold

If anyone has generated models before for prototyping, how much do
you scale them up so that your final product is the size you want?


  • darcy