I tried to foam my my armature today. It didn't go that well, in fact it kind of failed, but here's a look at what happened.
I started with my armature and checked that it fit and lined up in my mold properly before I started foaming.
I used a GM foam kit from Burman Industries. It comes with the foam latex base, foaming agent, curing agent, and gelling agent.
I brushed my mold with the mold release, let it dry and brushed the excess powder out.
Then I measured out the foaming ingredients, putting the latex base, foaming and curing agent into one cup and the gelling agent in another since it's added last. I made a pretty small batch, starting with only 75g of of the latex base.
I mixed everything, adding the gelling agent during the last minute, for a total of seven minutes.
I brushed the molds with a layer of foam before filling them, placed my armature inside, strapped the two halves together, and baked it in the oven for about four hours at 180°F.
After removing the mold from the oven, I trimmed the flashing off. This is when I realized how badly the foam had turned out.
My foam was really fluffy, and I mean REALLY fluffy. It was so light that it didn't seem like it would hold up. And as you can see from this photo, I was right. My poor, poor little raisin headed puppet. The weird thing was that the foam didn't wrinkle up like this in the belly, it would spring back when poked.
Well, most of it would spring back, but this is what happens when you pull a Pillsbury Doughboy too early into the baking period. You get a large dent that won't even pass for a bellybutton. All part of the learning process I say! I think the major problems came from over mixing and using too much gelling agent because the foam gelled really fast. I mixed everything in the garage, with the garage door open, so it was pretty humid and warm, which probably also contributed to the foam gelling so quick. In fact, the foam had already set up a bit when I placed the armature in, making it difficult to fit it in all the way.
BUT, trial and error are some pretty good teachers and I think my next attempt will be better. Or at least not have so many dents from my need to poke things that look squishy. I promise!