How to Work With Moldable Plastic





Introduction: How to Work With Moldable Plastic

About: We specialize in plastic molding materials and plastic pellets for hobbyists, crafters, players, fixer-uppers, makers or anyone who wants to try stuff.

Hello Cosplayers, Makers, and more. Thomas demonstrates how to use moldable plastic from Polly Plastics. Moldable plastic melts easily in hot water and can be used for costumes, prototyping, repairs and more.

Step 1: Watch the Video

Step 2: Safety Instructions

  • Be careful to avoid burns when working with hot water, hot moldable plastic, stove tops, ovens, heat guns and hair dryers.
  • Pellets pose a choking hazard for children under 3. Due to potential for burns, supervise children under 7.

Step 3: Gather Your Tools and Materials

Step 4: Heat the Pellets

  • Using a microwave or stovetop, heat water in a bowl or pan to above 150 degrees F. If the water is boiling, allow it to cool to prevent possible injury. You can heat the water with the desired amount of Polly Plastics moldable pellets in it, add the hot water to the pellets or drop the pellets into the hot water. If you are making a larger part, you may find it useful to start with a smaller number of pellets and gradually build up your part.
  • After a few minutes in hot water, the pellets will turn completely clear and begin sticking to each other.

Step 5: Remove the Pellets

  • Remove the pellets with tongs or a spoon and shake off any excess water. A sheet of parchment paper or glass makes a great surface to work on, preventing sticking. Take care that the hot plastic doesn’t stick to things you don’t want it to such as certain plastics (acrylic, vinyl, PVC, polystyrene, polyesters, ABS), fingernail polish, fabrics or metal.

Step 6: Form Your Pellets

  • With clean hands, begin forming the pellets into your desired shape. You can use your hands, craft with tools, apply onto existing objects or press into molds you have prepared. You can use a hair dryer to make final touches.

Step 7: Add Color If You Wish

  • For color, use Polly Plastics Color Pellets. Just follow the recipe on the Color Chart to get the color you want. Put the color pellets in the hot water with the clear pellets.
  • Or add paint powders or alcohol inks (found at craft stores like Michaels or Hobby Lobby) into the hot plastic while you are working with it. Or you can paint the part after it cools with acrylic paints or permanent markers. Without coloring, the part will be white. Spraying on a coat of primer for plastics will help adhesion and you can spray on varnish after painting to prevent flaking.

Step 8: Finishing Touches

  • Once you are satisfied with your creation, let it completely cool to take a strong, permanent shape. Cover it with cold water if you want to speed up the process. If you don’t like the outcome, re-heat and mold it again.
  • Once cooled, you can sand, drill, varnish or paint the part you have made. You can also Superglue the part to other things.

Hope you had fun. Subscribe to us on Instructables and also subscribe to us on YouTube to see all our videos. Look for more Instructables in the future and be sure to check out all our craft and moldable supplies.



    • Backpack Challenge

      Backpack Challenge
    • BBQ Showdown Challenge

      BBQ Showdown Challenge
    • Stick It! Contest

      Stick It! Contest

    7 Discussions

    I have never heard of this stuff. Does it melt or get soft one a really hot summer day?

    6 replies

    The air temperature has to get above 140 F, which is very high but temperatures inside a hot car could may cause some softening. Under normal conditions though, it is your typical plastic.

    any I can probably find it at any well stocked craft store? I have been looking for something to mold a chess set in. Plaster just seemed a bit fragile. Plastic would do nicely.

    You can find similar products in geek-toy/gadget shops, as it is not only aimed at the art community, but the makers and hackers :) You can find it in varying quantities on eBay too, under various names e.g. Polymorph. It is useful stuff to have around ...

    It's actually somewhat difficult to fiind and what is there is pricey. Our brand is not in retail but you can find it at We also carry silicone mold putty if you want to make a mold of an existing chess piece and then press the moldable plastic into your molds.

    I saw that you are in Saginaw. We drive past there often--I hate the bridge.