This is the first in what I hope will be several FX material guides.
Prosthetic Gelatine is a very effective material for prosthetic make-up, it is cost effective, reliable, durable and brilliant at capturing fine detail. What’s even better though is that if you get a bad casting (which can happen no matter how good your mould is) then you can simply remelt the gelatine and cast it again!
Prosthetic Gelatine can also be used directly on to the skin to create burns and scarring. Although you do need to pay very close attention to the temperature of the gelatine when you apply it to the performer as you can cause REAL burns and REAL scarring.
One of my favourite things about the material is the way it moves on the skin, it also has beautiful transparency when painted with IPA make-up palette systems.
You can purchase Prosthetic Gelatine from numerous FX Make-Up suppliers (Mould Life, Guru Make-Up Emporium, Nimba Creations, Brick In The Yard etc) but you can also make it yourself and I will share my recipe later on in this post.
I personally love Prosthetic Gelatine for anatomical prop making. It really captures details and whats more, you can heat a metal tool in boiling water or over a candle and sculpt in meaty details DIRECTLY in to the gelatine.
|Severed finger prop by the author, cast in prothetic gelatine.
Another favourite thing of mine is that Prosthetic Gelatine is hypo-allergenic, it is very rare for people to have allergic reactions to it.
Of course, there are draw backs to it. For example heat and moisture will affect the appliance and cause the gelatine to sag and melt. Also each prosthetic can only be used once.
A really nice thin about using prosthetic gelatine is that you can dissolve any edges in to the skin by simply dipping a cotton bud (Q-Tip) in to some distilled Witch Hazel. More experienced artists will know this is similar to encapsulating a silicone prosthetic in cap plastic (ie Mould Life’s Baldiez) and then dissolving the edges with 99% Alcohol.
My Prosthetic Gelatine Recipe.
My recipe for prosthetic gelatine is VERY simple and creates a very soft, flexible material. It is much softer than a lot of prosthetic gelatines but I believe this gives greater flexibility and realism.
I will not put quantities for the sake of simplicity but I will include the ratio I mix the materials to.
Two parts of powdered gelatine.
Two parts of Glycerin BP. (Glycerol)
One part warm water,
Half a part of runny honey.
In a microwave safe bowl I add the Glycerin, water and honey and heat in the microwave until it is hot, NOT boiling.
Once it is hot I VERY SLOWLY add the powdered gelatine, small amount at a time, waiting until each part is dissolved before adding more.
It is heated in about 10 second bursts in the microwave, stirring thoroughly after each, until the gelatine is fully dissolved and the mix has a smooth, runny texture. It is then left to set until you are left with a solid, rubbery product that can be melted in the microwave and cast many times.
NEVER let the mixture boil when you are heating it. It will degrade the gelatine, rendering it useless. Also always check the temperature before applying it directly to the skin, it can cause severe burns.
A lot of FX artists add sorbitol to their mix, but I am not a fan of this as I feel it gives too solid a material.
Once it is molten I add pigments and flocking to create a rough flesh tone. Saving time in creating the finished prosthetics.