answers:
I forget exactly how thick it is. I wanna say 1.3 mm. It's about skin dive suit thick. What I do is take the raw material, and pull it over my bodycast. then pin it up. I barely use any pattern because this thing has to fit tight, but the key is evenly tight. Having a really good head-to-toe bodycast is key. I let it sit for a few days, then go back and tighten it up if necessary. even tension is so important. Not neoprene, but a smooth skinned sheet rubber backed with spandex. I also have to treat the rubber before I use it otherwise glue will not hold. I use a diluted type of rubber cement for glue. I can also position the seams exactly where I want them. The seams on this suit are more like where they placed the seams on Batman forever. the next copy I do, I will place the seams where they did. But I have that control because I am doing it from scratch, and the bodycast is invaluable.
I read the interview where Day Murch talks about vegi based neoprene. I actually asked some manufacture about that, and they pretty much scratched their heads. Sometimes you gotta take some of what they say in interviews with a grain of salt. I met Day at the batshop in 94'. If I ever talk to him again I'll have to ask him about that. He recommended a glue that I tried, and I could not get it to hold anything in place. dunno.
flammability: usually the stunt guys get the foam latex reject pieces. Foam latex is very light - depending upon how the foam was ran. I'll get into that in a minute. In the scene where the stunt guy jumps off a building in flames, he wore a silicone suit. Reason. both urethane and foam latex are highly flamable. Foam latex uses sulphur as a curing agent, and as you can imagine, it would burn very rapidly. Urethane has petroleum by-products. So the least flamable is silicone. Downside with silicone: the weight. roughly the weight of water. Now about the weight of foam latex: In the procedure there is what is called a whipping cycle. How fast, and how long determines the "rise" of the foam, and the softness, and elasticity. I could actually not whip it, and it would be as dense as a hard urethane, or silicone. but I prefer to make it as soft and as light as possible. Looks better, feels better, moves easily. What you are doing is whipping more air into the rubber mixture, but the cell structure is still very fine, and even. Foam latex is an art into itself. Having the choice of making these out of any material I want, there is no question about using foam. Hands down the best for these type of costumes. Foam really reinforces well with fabrics like 4 way power net. which makes it almost unrippable. There are also more chemical, and mechanical techniques that will increase the durability of the material structurally. My suit looks dense mostly because of the highly mechanical/pristine sculpture. It is not very dense at all. startup costs on foam latex suits of this nature is very expensive. You need some fairly large industrial mixers, injection guns, and ovens.
The whole process simplified, is: Make a bodycast of yourself. a darn good one from head to toe. then you will need a master mold of it to crank out several copies for various reasons(fitting, injection, storing). Now crank out a copy from just above the knees up. this will be the armature/core for the torso. Do the sculpture. make the mold, remove the clay. Now add the powernet to the core. place the mold back on the core. Mix the foam and inject inbetween the core, and the mold. Now bake the foam in a very large oven. Take off the mold, wash, dry, trim, and glue onto the undersuit which is on a bodycast. done. Now note that I am simplifying the whole process here tremendously, this is just a rough overview.
As proximo said, everything I do I build from scratch. even the boots. I will have it done soon, with gloves, belt, and cape/cape clips. Massive project these suits are if done like this. But if you're really into this, well worth it.
One other thing. there are fire-proof materials you can add to foam latex. Not sure why they did not research that, or if they were even aware of it.
Many more pictures to come. Keep checking the boards. this is the suit sitting on the bodycast just after I wore it for the pictures.