How long does it take for Foam Clay to dry? Can I speed it up?
At a quarter of an inch thickness, it takes approximately 48 hours (two days) for Foam Clay to dry. If your piece is thicker, we recommend waiting up to a week before performing any deep cuts, or sanding. After this point the surface is strong enough for painting and or priming.
Foam Clay is an air dry clay, so putting your piece under a heat source is not recommended. Doing so can dry the surface too quickly for the inside layers to keep up, resulting in uneven surfaces. Do NOT dry your items in the oven, under sunlight, or with a hair dryer. The result will be a dried skin, and then the inside will bubble and puff up OR shrink down and collapse
How long can I work with Foam Clay before it starts to dry?
You have approximately 25 minute to half an hour of working time before the surface of the clay begins to dry out and ‘skin over’. This will make it more difficult to blend any seams or smooth the clay over. If you need to rehydrate your clay piece, adding a little bit of water to your fingers and working it into the clay will extend its softness.
How do I prime, seal, or Foam Clay? Does it need to be heat sealed?
You can use a variety of mediums to seal your piece. We highly recommend Flexbond for priming dried Foam Clay.
Painting a Foam Clay piece is similar in feel to painting EVA foam. While you can paint foam with acrylic paints, for the best results we recommend sealing and priming your piece before painting.
Heat sealing is not required, as there are no open pores to seal shut like in EVA foam.
Is Foam Clay flexible? Does it crack? Does it Shrink?
The approximate shrink rate is 1-2%. This is only noticeable when placed in a silicone mold as the clay pulls from the edges while drying. This does not have any negative effect on the amount of detail that is retained.
Once dry Foam Clay is NOT flexible. Thin pieces can easily be snapped so it is best to use Foam Clay over an armature or support.
Can I cast molds with Foam Clay?
You can press the Foam Clay into silicone molds powdered with cornstarch/baby powder, or plaster molds. The thicker the piece, the longer it will take for the mold-facing side to dry.
We HIGHLY recommend placing silicone molds filled with Foam Clay in the freezer and demolding once the piece is frozen as even after using a mold release the fresh clay can stick to the mold.
For plaster molds we do not recommend trying to demold until the piece is completely dry. This can take several days to a week.
How do I keep my Foam Clay from drying out?
Keep your Foam Clay in an airtight container at all times to extend the life of the clay. When well sealed, the shelf life is approximately a year. To avoid a "skin" forming on the top of the clay we recommend cutting a circle of plastic or plastic wrap. Spritz water on the surface of the clay and press the plastic down over the clay.
If you have a small amount in a large container, you can wrap the clay in plastic food wrap inside the container, or transfer it to a ziplock bag. If your clay is becoming stiff, kneading a touch of water back into it will help refresh the clay