Tuesday, August 5, 2008

Lifecasting Silicones

There's a lot of talk these days about the various lifecasting silicones on the market. I've played with my fair share of these products so let me see if I can cut through some of the hype.

First of all, in the interest of full disclosure, I am a Polytek distributor and I favor Gel-10 for many applications. That said, I do have a somewhat open mind.

Here are the major players for silicone Lifecasting:
1. Mark Prent's Ply-o-life
2. Smooth-on's Body Double
3. Artmolds LifeRite
4. Polytek's Gel-10

There are some others but these are the ones most accesible to the general public.

Ply-o-life used to be THE lifecasting silicone. Mark has an excellent video on both the headcasting process and body casting. The main complaint I have heard about Ply-o-life is the price. Now that other silicones have come out that do the same thing Ply-o-life is a bit out of reach for most consumers.

Smooth-on released Body Double in summer of 03. While I found Body Double to be a good molding product overall, I found it to be expensive (though cheaper than Ply-o-life) and it had an amazing ability to stick to the finest of hairs even with vaseline.

Artmolds released Liferite in 04. Liferite is a nice, firm silicone for lifecasting (which is nice since body double is fairly soft) but the 10:1 mix ratio complicated the mixing process. I have several lifecasts that were done with Liferite and the results were great, however the mix ratio made me hesitant to use it on large projects.

Platsil Gel-10 is marketed as a general purpose FX grade silicone. My first thought was that it was entirely too soft for lifecasting as it is a shore A10 with about 960% elongation. For a headcast you really don't want a rubber that soft or stretchy as the mold will distort durring casting. Then I found out that adding Polyfiber to Gel-10 stiffened it a few points and lowered the stretch. This addition of polyfiber makes for a radicaly different material. I have since used this method extensively to make many different types of body casts and head casts.

While I prefer Gel-10 over the other products mentioned, let the record state that a big part of this skill is the craftsmanship, not thet silicone. The silicone will not make itself into a mold. Your competency as a moldmaker/lifecaster will ultimately determine which material works best for you. Gel-10 has been great because it is versatile. You will find that when a product may be manipulated with other additives it allows you a certain freedom as a craftsman.

1 comment:

Anonymous said...

What about mouldlife lifeform?