A few casting ??s

What do you guys use to make your molds when casting resins?

Want to do some round shifter type molds but can't figure out how to the "ball" out of the mold? Will latex stretch that much? Oram I going to have to do a 2 part mold? But it will leave a seem?

 

might try some thing like this?

http://www.alumilite.com/howtos/TailLightCastingNoEquipment.cfm

 

http://alumilite.net/Category.cfm?Category=Silicone Rubber

 

Here is an additional supplier for your casting needs.
http://www.smooth-on.com/
Their materials are high quality and they have helpful how to videos. Also they have nice trial size portions which in most cases are more than enough so you don't have to buy large quanities when you might not need it.

Smokey

 

I agree. Smooth on has equal part mixing with make it easier to mix by volume instead of un equal weights. No need for an accurate scale. I sculpted and reproduced a complex tiki shifter with this stuff. Read up on making 2 pc molds. they are easier to deal with but a little time consuming to make.