For starters we bought all of our supplies at Michaels with a total cost of about 28 bucks.
This is an alginate analog called "Mold Maker". Pretty standard stuff, if not on the cheap side. The performance of this product leaves quite a bit to be desired, but we made it work for our purposes. I'd highly suggest making it at 1/2 strength and using multiple layers for the best results.
This is my lovely assistant Bonnie. Posistioned right off screen is the gun I'm holding to her head.
Step 1 - When prepping the model we used a head band and a release agent to keep the alginate and plaster out of her hair.
Step 2 - This is the alginate layer that I used on her. This was mixed at full strength and set incredibly quick as noted by the cold oatmeal-like consistency. It definitely worked a lot better when we back and used a dilluted mixture.
Step 3 - It's hard to see here, but before the alginate fully sets I pushed several bits of cotton into material so that the plaster bandages would have something to bind to and keep the entire structure together.
Step 4 - We used a prepackaged plaster bandage system to create a mother mold for the alginate.
This is the finished mold after we carefully demolded de-model. We left the nose section open during molding as this was her first life-casting, but she did awesomely regardless.
The rest of these shots are of me going through the same process. I tried to get a little better resolution around the nose using the "straw method", but it was uncomfortable as hell and was a bit more difficult to detail in finishing. Having the straw shoved half way up my nose every time Bonnie would bump it didn't make things too pleasant either.
Next we filled both molds with a craft plaster called "PermaStone." (Hardly) Then they went into the oven for about an hour and a half at 200 to speed up the cure of the plaster.
These are the rough casts we pulled from the disposable molds.
Chiseling out some basic shnoz shapes.
The cleaned up facial casts. They still could use a little TLC, but since we're only focusing on the forehead and nose area, these should work just fine.
Since I'm a 1000 miles from home at the moment, I don't have access to any of my tools or supplies, so I grabbed a cheap 3$ block of clay while at Michaels to do some simple visualization of what the prosthetic might look like after final sculpting. Mine looks okay, but grover on the other hand. Esh, it'll need a little more work. The stark contrast of the clay to plaster really throws off the effect as well. That and someone was feeling awfully creative with their face cast after we got back from seeing Avatar.
The next step once I get home is to do a proper sculpt on these using Chavant clay. It's much denser and should adhere quite a bit better to the surface of the plaster. And it doesn't make my hands look like I've been molesting a smurf. After that, I'll grab a couple trial kits of Eco-Flex and a tin or two of psycho paint, and see what we can do to pull the wearable prosthetic pieces.
Onward and upward.