December 13, 2019

Yes, that’s right. You can make a silicone mold of almost anything! Some things require specific preparation and there are a few things you might not want to use. Otherwise, the mold making possibilities with AeroMarine Products silicone rubber are endless.

Let’s start with materials that you don’t want to use to make a silicone mold without a lot of careful preparation. Since silicone is made of silica, it bonds to anything with silica in it.  Accordingly, things like glass, quartz, and certain ceramic glazes can’t be used without being sealed or painted first.  If you are unsure if your original piece contains silica, find a small, unobtrusive spot on it, apply a dab of AeroMarine Products silicone and see if the silicone peels off once it has cured.  If the silicone sticks, your original has silica in it.  In this case, you must seal or paint your original part before molding it.

Materials such as wood, fabric, plaster, foam, and concrete make excellent originals.  However, they also must be sealed or painted before using because they are porous and can be difficult or impossible to remove from the silicone mold. AeroMarine Products silicone will pick up the finish of your original, so make sure you use a sealant/paint with the finish that you want. 

foam sticks being sealed with a clear urethane spray coating

You can also use non-sulfur clay for your original. Do not use a sulfur-based modeling clay because sulfur inhibits the cure of AeroMarine Products silicone. Always check the label before using any type of clay in your mold. Air dried or kiln fired non-sulfur clay is fine to use as long as you seal or paint the clay first.

Even organic materials can used as an original. I had a friend mold a fish! It had to be frozen first so that it held its shape, but it worked just fine. Any organic material must be as dry as possible and sealed, if feasible. Leaves, grains, acorns, horns and antlers are popular organic materials to mold with AeroMarine Products silicone.


You can also use several different type of material glued or fastened together as your original! For example, if you have a chipped figurine or vase, you can use modeling clay to fill in the missing parts. Or, if you have a sculpture made of wood and want to glue lace around it, you can do that. Remember that AeroMarine Products silicone will pick up the finish of each type of material in the mold. Be sure to seal or paint the whole piece first for a uniform finish.

There’s only one thing that you never want to use as an original part for your AeroMarine Products silicone mold; an irreplaceable object! Most things survive silicone molding undamaged.  Unfortunately, things do happen and you don’t want to break your mother’s antique vase when making a mold of it.  Use a replica, not an irreplaceable original, so that you won’t worry if something happens.

The fabric part of this shoe absorbed the silicone and ruined both the shoe and the mold

So a quick recap, what can be used as an original part for AeroMarine Products silicone mold making?

Almost anything that isn’t irreplaceable.  Materials that are porous or containing silica must be sealed before molding.  Also, originals that are made from a variety of different materials should be sealed or painted first if you want a uniform finish on your castings.

If you have any questions about this mold making process or any of your own projects, give us a call at 877-342-8860, contact us through our website or drop us an email at

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