I bought a bunch of masks on ebay and i want to fill a few of them with either great stuff or 2 part foam im just a little concerned with them looking "bloated" after. anyone have any ideas of how to do this properly?
Not having done this, but having experience with great stuff in molds. I would say go slow with small amounts. Multiple layers. Also get yourself a spray bottle. Apply your layer then spray it with water. This will make the great stuff expand fully in minutes. Considering that this is a hands on operation you want the speed.
Alternatively you do know that you can pickup stryofoam heads at beauty shops for around $4 each? Might be more expensive solution, but your masks wont be stuck and you get that hole in the bottom for easy mounting.
Anyhow, if you do end up doing this, let me know! Would be interested to see how it goes.
I have used two part foam with no problem. I put a plastic bag from the grocery store in the mask and fill the bag in the mask with the foam so it won't stick to the mask in case you want to remove the foam later. When the two part foam is expanding you can push on the mask to shape it the way you want and make sure it doesn't look bloated. The two part foam will set in about 5 minutes so don't have to wait long. Great stuff can take for ever to cure if you don't do it a little at a time and do what Bubbles suggested about spraying it with water to force it to cure faster, that could work too. If you can get your hands on two part foam it works a lot better. Two pound should be fine and it will expand a lot more and be lighter.