Foam can also release fumes even over time.
I had a college teacher who worked on many props for Star Trek tell me to never use expanding foam on anything that will be near the face. He is very adamant about teaching such things. He also told about a story of them making a moon for the backdrop once out of expanding foam. The prop seemed stable at first, and a women spent days painting it with meticulous details. But it deformed and the foam warped, causing the entire thing to continue to expand, and thus cracking and demolishing the prop into a useless piece, ruining all of her hard work.
I always think back to home construction. You see the expanded foam oozing out of cracks and stuff to sometimes ridiculous degrees, but I don't think it was anywhere near that bad of blowout when they were concealing it, the foam doing what it wanted after the fact.
Some alternatives if Bondo isn't an option, is some stuff I am experimenting with now. I have not used it fully yet, so I can't guarantee to you this will WORK, but it look promising.
So without further or due, here is my dump of alternative costume making methods.
It is very light when cured, lighter than Bondo, but has a lot of tiny air pockets so the final coat would need to be something like fiberglass or oodles of primer to fix that. When working with it, it is very tacky so details are impossible on the first layers.
This stuff has a nice consistency when working with it, and feels air light in the hand. From the demo images it shows it is strong enough to stand on, but light enough to hold with one hand. I used this in the snout of my Skirmisher helmet cast. For the helmet it felt way too heavy considering how much else I have to add to it, but it may have been the thicker plastic that was also down there, so I don’t know if it is really light or adds some heft. Nonetheless you can't work in large amounts at once, so many applications of small chunks.
This option is light, inexpensive, but requires skill and would not really work with the paper craft framework you already have made. Some are using it on the site already, and it can look great with patience and practice.
Here is the other user's thread with it-
http://www.405th.com/showthread.php/35889-ODST-Foam-WIP-%28Pic-Heavy%29-GySGT-Buck
-----
Elmer's Glue and Cheese Cloth
I have not tried this, and I would NOT recommend it unless you are on a super tight budget, as it could be a total BUST, but I have seen people use cheese cloth, or other thin porous fabric, dipped in Elmer's glue like fiberglass. However many many layers would be needed to thicken enough to sand, and the fabric may make sanding ridiculously silly looking. Glue is also brittle when dried, so if it is dropped or sat on improperly without enough structure it would likely shatter into a sad little mess. So even if you decided to risk things and go with this? Make the hip, thigh, and foot pieces out of something reliable so sitting and walking don’t cause a demolish.
-----
As with any of these, ordering test/sample amounts may be a good option first, to see if you even like it. The costs also can seem scary on the Smooth-On products, but I try to take into account the pros that go along with it such as the reduced weight and the ridiculous strength. I am not a strong person at all, I don’t want to lug around a heavy costume all day! I tried making Car Bondo hooves once for a minotaur and they just felt like led on my feet.
Either way this was my dump of armor making ideas that I can think of offhand that don’t branch out into the insanely expensive methods of Styrene, Vacu-Forming, and Molding.
epped
