Fiberglass Molding

Joseph Humpston

Hello Guys! So, I'm very interested in learning to make animatronic creatures, and I know that the under-skull in most animatronic creations is made from fiberglass. Right now I'm already familiar with the process of making negative molds out of plaster of Paris, and I also know how to use polyester resin. However, I've never actually used fiberglass to cast an object from a mold.
I guess what I'm actually asking is what kind of release agent should I use in casting fiberglass with a plaster mold?

Chris Ellerby

Hi Joseph,

PVA and waxes are common releases when working with fiberglass.  There are a lot of great fiberglass molding tutorials on YouTube that should get you stated.

Best of luck!

/Chris

Chris Ellerby

Absolutely.  When casting a semi-rigid piece like fiberglass a flexible silicone mold is great.

/Chris

Joseph Humpston

@Chris Ellerby  Thank you!

Also, could I make a fiberglass cast in a silicone mold?