what to use as a mold for silicone

[scrymnstr]

I am wondering what to use as a mold for silicone masks/ prosthetics?

[Allen H]

Fiberglass

[sickNtwisted]

Fiberglass for large projects such as masks and you can use hydocal, ultracal 30 and rigid urethanes for smaller pieces such as appliances/prosthetics.

[derekatronic]

The recommendation I've gotten - even from full-time moldmakers - is to contact smooth-on and/or polytek (or one of their dealers), ready with details of your project. They know their products best. Fiberglass is a good suggestion, but there are other resins that might work just as well w/o fiberglass and would be much less hassle, and there's a reasonable chance that silicone isn't even the ideal casting material for your task! It's worth looking into.

smooth-on homepage
polytek homepage

Best of luck.