Greetings, all -
Can anyone suggest which foam latex might be better for a stop-motion puppet, prosthetic grade or animatronic grade?
I am guessing cell size and elasticity might vary, but have never actually worked with either before.
I have been looking at the Monster Makers website and this option was something I had not considered.
My understanding is it is not so much the quality or properties of the final piece that is the difference but the chemistry difference in what allows it to setup and gel properly. Prosthetics you are usually just casting alone so you have more control and less worry in the right conditions. When it comes to puppets and animatronics is that you will more than likely be embedding some sort of support or skeletal structure of different materials (with their own chemistry and contaminants) that could prevent certain foam formulations from gelling properly. In this case the animatronics grade is more forgiving.
I used to use a hot foam product by R&D Latex many years ago. I think prosthetic grade foam makes finer edges, ideal for make up prosthetics. It would seem that animatronic grade would be better suited for stop-motion models. Email Monster Makers to be sure.
Hot foam is such a bear to work with that I have been looking into the new cold foams. That might be a option for you as well. The only drawback to cold foam is the short working time of 30 seconds, but that should be plenty of time fill a mold.
Keep us posted on what you decide on and how it works.
I was just looking at the monstermakers site. I have never used their foam before but they say it is the old McLaughlin formula. I have used that before way back when. The chief difference they talk about between the two grades of foam is that the animatronic grade will gel at a higher PH, so whipping all of the ammonia out is not as critical. They both describe the foams as "microcellular" so I would assume that the animatronic grade is not necessarily a coarser grade. It does sound easier to use and if you don't have much experience with foam that would be a good thing. But you will need a proper scale and a mixmaster to whip up the foam with. You also don't really want to use your kitchen oven for foam latex unless you like the taste of foam rubber. Good Luck!
Good information there!
I haven't thought through the kitchen oven dilemma . . . .