DIY Silicone Gap Filler Craft Mold

DIY Silicone Gap Filler Craft Mold

This tutorial shows you how to make a craft mold for polymer clay or jewelry making using Gap Filler or silicone.

What you need

Gap Filler / Silicone (Found in hardware store)
Corn Flour
Item to create mold


For this mold you only need 2 ingredients. Gap filler or silicone (from the hardware store) and corn flour.

These DIY molds are quick to make and can be used for casting jewelry and poly clay shapes.

We used a shell to create our mold.


Start by mixing the two ingredients together. You need the paste to be the consistency of a dough. It shouldn’t stick to your fingers and should come together. Once you are able to roll it into a ball it is the right consistency.

Shape your ball into a rectangle or square a 1/2 inch thick (depending on the depth of the item you are casting)

Then simply push your casting item (shell) into the dough.  If you are not happy with the impressions just roll it back into a ball and start again.

It will take 2-3 days, depending on the weather to dry.


  1. I’ve used this method and it’s great, had loads of different shaped flower buttons and other items, pressed them into molding, gently removed from flexable molding and hey presto you can make many more, brilliant idea. Thanks for sharing

  2. I am guessing corn flour = corn starch? in the US?

  3. I think this is rather cute.But what to do with this afterwards? You also say you can make Jewelry with this?

What do you think of this project? Let us know!