ComposiMold Questions and Mold Making Advice

Posted by ComposiMold on 6th Oct 2022

ComposiMold Questions and Mold Making Advice

Here are some questions we've received that you might like to read about.

How porous is the ComposiMold material?
It's food safe, but does it hold on to water (I'm asking because I want to avoid mold)

ComposiMold by itself won’t mold, but any food particles left in it might. So after use, clean it well before storing. To keep it food safe condition after use rinse the ComposiMold with cold water to remove any food particles. Re-heat the material to 160-180F and let it sit out until it has cooled to room temperature. To store the ComposiMold place it in a sealed bag or container.

I have a painted wooden hand that is not quite life size. I would like to make a mold from it, though I'm not sure what that would be yet, I have a 40 oz container of the ComposiMold Orginal, but do not have any other materials like the Mold Release and Bubble Buster?


Do I need to seal the wood? And if so, what with?

Do I need Mold Release and Bubble Buster?

Yes, great application for ComposiMold. depending on the shape/size of the hand 40 oz. should be enough for the hand.

Yes, sealing the wood is a good idea. shellac or spray-on urethane works well to seal. You can also wipe glue over it and let that dry. You can also mold it without sealing and it should also work, but the sealing helps reduce the bubbles from seeping out of the wood.

Use vegetable oil or mineral oil for a mold release, so you don’t need to buy anything extra there

Bubble Buster would be helpful, but I’d try it first without it, and if it doesn’t work, then get some. You’ll probably be fine without it. Use a paperclip or toothpick to pull any bubbles that are sticking to the surface of your original when making your mold. Because the ComposiMold is transparent, you can see the bubbles on the master part.

Another thing to help is to let the ComposiMold cool a little before pouring it (still liquid, just cooler-a little thicker) over your shape that way it’s a little thicker and fewer bubbles.

And as I think about this…something I typically forget to do is to glue down the hand so it doesn’t float…so use a little hot glue to hold it in place.

I usually make 2 part molds with silicone by using playdoh to embed parts in half. But ComposiMold reacts with the water content in playdoh. I prefer make 2 part molds most of the time, and only pour a one part and cut when it makes more sense.So is there another method to make 2 part molds with ComposiMold?

Plastilina clay is a good choice and most have a melting point of 150F, and as long as the ComposiMold is below that when you pour there won’t be an issue. You can also chill the Plastilina in the freezer before pouring to be extra certain that it won’t melt. If you do want to continue using playdoh I would suggest using a mold release and also chilling the playdoh to help to reduce the sticking (but not eliminate it completely).

Can you use ComposiMold to take a mold from a wax sculpture? Such as microcrystaline wax?

Yes, the microcrystalline wax will work really well to mold. Just be sure the ComposiMold is lower temperature than the wax so when you pour it over and around the wax shape it doesn’t melt the wax. Microcrystalline wax melts at around 15 F (or so) so you won’t have to worry about it melting at all.

To cast wax in ComposiMold, ComposiMold works really well with low temperature waxes like soy wax, many paraffin waxes, up to about beeswax (160ish degrees F). For higher temperature waxes you want to chill the mold (put the mold in the freezer for a bit) first before putting in the wax so the wax cools before it melts the ComposiMold. This works really well with many paraffin waxes.

Microcrystalline waxes typically have a melting temperature a bit higher, so I recommend for casting it, moving to our ImPRESSive Putty (also re-usable) that can handle the higher temperatures more effectively….up to about 200 F without chilling and about 220 F with chilling. This makes it well suited for many jewelry making options.

Here’s a couple videos of the wax molding and casting processes:

For beeswax and ComposiMold: here’s some candles:

And ImPRESSive Putty with wax:

And we have an ebook on candle making with ComposiMold that you can check out.

I recently found an old vintage frame that I thought was very pretty and perhaps worthy of some restoration. I got the frame out of a trash bag, so, I really don’t want to invest a ton of money into repairing it. However, I have other items that need similar repair, (not very many, but a few) and thought that it would be good to learn how to so these types of repairs! I am not sure what product or products that I will need to purchase to complete a repair project?

Great application! You’ll want some ImPRESSive Putty Mix and some resin. I think I’d go with a white and then paint it afterwards with acrylic paints to match. Here’s a video of us fixing a frame, that I think would help you. It’s pretty easy, although if you’ve never made a mold before may take a try or two to get it right (another nice reason for the putty is you can reform it).

Frame Fixing:

For material:

Depending on the size, I think a 6 oz Putty would be enough:

To reduce cost, add about 20% by weight or volume some plaster of paris or even regular cooking flour into the resin to reduce the amount of resin you use. You can do this if you’re using epoxy resin, but you can’t with urethanes because the polyurethane is more sensitive to moisture.

I have your ComposiMold product using it with your clear cast resin to do two part molds of 1/200 scale ww2 planes, so most are fairly small. The idea is to paint around the plane to leave the canopy clear. It gets pretty messy with trying to elastic or tape it up and I obviously need more practice.

I also have the small demo impressive putty and am thinking of buying a large sized one to attempt the above as I see you have a demo now showing two part molding using impressive putty! However, I don't seem to find anywhere about using impressive putty with clear cast resin epoxy. WIll this work for me?

Impressive Putty does sort of works with the clear casting plastic with one issue, you won’t be able to make anything super clear. The ImPRESSive Putty will leave a frosty white haze on the clear part. If you are adding pigment you won’t see the haze but if you are trying to make something clear you will. The quality of the piece is not affected so if you do want to add pigment or paint this would be a great option.