Clay Pour

Here's the clay pour process mentioned in the Gel-10 lifecasting video. In order to make a prop head or likeness of an actor it is best to first cast up a clay positive, refine it, alter the expression(if needed), and remold it. In my DVD "Fundamentals" I go into the molding process.

Chavant may also be used for this process but it pours a lot thicker so care must be taken to avoid surface bubbles. Also, REALLY hot Chavant may cause outgassing of the silicone as all the little micro surface bubbles release air. This causes a sponge-like texture on the clay surface. No bueno.

If you are making a clay cast into alginate make sure your clay temp. is below the boiling temp. of water. If not, the clay will boil the water out of the alginate surface causing distorion or adhesion.

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.

Here's the cast video for those who found the blog first:

Gel-10 Lifecast Prep

Well I posted the new Gel-10 lifecasting video to youtube. For those of you who are interested in trying out a Platsil Gel-10 lifecast here are some prep pointers:

• Use a plastic bald cap if possible. A woochie latex cap will work but will cause some cure inhibition at the cap/silicone interface. For the video I use a latex cap. In warm weather the cap material won't much of an issue as the silicone will set fast enough that little to no inhibition will occur if the cap is released with a liberal amount of vaseline. In cold weather Gel-10 will set slower and thus may cause more inhibition problems with a latex cap.
• Vaseline is the best seperator. Don't skimp. You have lots of little hairs on your skin that alginate wouldn't grab but Gel-10 will. Eyelashes, eyebrows, and other facial hair should recieve a liberal coat of vaseline.
• An experienced model is important. You cannot rip off a Gel-10 lifecast the way you could an alginate mold. Start with a face mold.

Gel-10 Headcast

Gel-10 has been my material of choice lately for lifecasting. For detail critical lifecasts for prosthetic work this seems to be the best way to go. Not only do you have a reusable mold but the weight is less that alginate which causes less ditortion to the subject's face.

I will soon be posting a Gel-10 lifecasting video(s) on youtube. I will be breaking in it up into 2-3 secions depending on length. I will also demonstrate pouring up a PT Flex 20 casting with foam interior. PT Flex 20, as luck would have it, is an almost perfect flesh tone right out of the bottle.