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This page is to provide information on the process of Life casting, this is taken from our own experiences. There are many other effective techniques and products
that will work. We will continue to add information to this page as the work progresses. Please send us your comments or suggestions on our efforts to provide informative information.
No life cast would be possible without the model, so that is where our information begins. When deciding on placement of the model for the casting process be sure to be considerate and
remember that the model has to remain in that pose until the mold is complete. We suggest that you let the model select several poses that are comfortable to them. Photograph your model in each
of those poses from at least three different angles, we find this very helpful in later determining a final effective pose. All Photographs on this page are (C)opyrighted and require our written permission before use
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Model Release
You should be sure and obtain a model release before beginning the photo or casting process. A model release is
protection for both parties and should be included in any contract with the model. Click Here for a
copy of a standard model release should you need it.
Preparing For Molding
We used silicone(GI-1000) to produce this mold (This Product is Not Labeled Safe For Skin Contact!!) We
Recommend you purchase a skin safe silicone (Art Molds / LiteRite Silicone
) . Silicone produces a durable mold with outstanding library life. When using silicone for life casting be sure to run a reaction test on the model's wrist a few days before the actual molding session, this insures that there will be no adverse reaction when applied to the body. The advantage to using silicone over alginate is the ability to use the original mold repeatedly without having to make a second mold from the first positive, as would be necessary
when using alginate. The silicone is pre weighed in one pound batches and set aside The catalyst (we use ultra fast catalyst) is also pre- weighed and set aside. Our catalyst ratio is
12% of the silicone by weight, this offers a 10 minute pot life and a 20 minute cure time. Since silicone will bond to itself in the cured state we can work in small batches to cover the model.
Covering the front upper torso from the neck to the waist requires 5 lbs. of silicone, this produces a mold 1/4 inch thick. Cab-O-Sil may be added to the silicone to thicken it, (this will affect the pot
life and cure time) so a little experimentation with the catalyst is required. The mother mold is made of plaster, we use cheese cloth as our reinforcement, you may use pre-coated plaster
bandages instead. Cut up the cheese cloth in various sizes ahead of time this eliminate the necessity of stopping during the molding process to cut pieces to fit. Place you model in the
position for molding , look for any problem areas that might arise during molding. A thin coat of petroleum jelly is applied to any areas of the body which contain hair, the rest of the body receives
a coating of lotion (Vaseline Intensive Care). The silicone and catalyst are mixed and applied to the model. The silicone will tend to flow slightly so start at the highest points and work
down, the second and third coats will tend to flow less than the first. The second coat can be applied as soon as the first coat has tacked off (when it does not stick to your finger)(about 10
minutes). In areas that will receive high stress during de-molding cheese cloth may be worked into the final coat of silicone. A thin coat of petroleum jelly is applied to the silicone mold
just before the plaster mother mold is applied (this will insure easy removal of the plaster mother mold. Once the plaster has cured the mold may be removed from the model (under normal conditions
approximately 45 minutes will have elapsed since the first coat of silicone). The silicone mold may be used for casting within the hour, however it does not reach it's final strength for 24
hours.
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