Tuesday, August 28, 2012

How to make a cheap hot box

Oil based clay comes in differing degrees of firmness. If you live in Colorado have your studio located in the basement, you'll find that even extremely soft clay will be very hard when cold. You could warm the clay in the microwave, as I've done in in the past, but inevitably you will end up getting burned when you squeeze a block of microwaved clay that seems firm on the outside but is a pool of molten lava on the inside. Enter the hot box.

There are a lot of different ways to make a hot box to warm your oil based clay. Tuck Langland has a very nice one that he makes from an old fridge. But you can also go very low tech, as I did here. I simply went to the dollar store and purchased a styrofoam cooler for $1. I also got 3 aluminum disposable pans for $1.

 I turned the cooler on its side and traced around the dome of a cheap shop light. Next I cut out the circle I traced using a sharp knife - being sure to cut 1/2" INSIDE the circle. I placed a 40watt bulb in the lamp and place it on top of the cooler. Since the circle that I cut out is a bit smaller than the lap - I sits just on top of the cooler.

Finally I took some cold, hard chunks of jmac classic clay and tossed them into one of the pans and slid it into the cooler and closed the door (which is really the top of the cooler). Within 10-15 minutes I have warmed clay.

This isn't perfect - it's kind of small and the center chunks of clay get melted while the outer chunks warm less - but for $2 and a lamp I already had, it sure beat sore hands from trying to use cold, hard clay or burned hands from lava-melted clay.

Yes - I know that the old, hot lightbulbs may be be a thing of the past and hard to find soon - but I imagine that I can get creative and find another heat source in the future - for now, this is great for smaller budgets, smaller space and smaller amount of working clay fast.


  1. how to make Jmac clay because i life in the netherlands. Please write me back at;hatlatietla@hotmail.com


    1. Reno,
      J-mac Classic Clay 2AB200 Series is a sulfur-free oil based clay available is soft, medium and firm. I buy mine locally in 10 lob slabs from Sculpture Depot - but it is available many places (U.S.) and on Amazon.com.

      You may be able to ask the manufacturer where the closest distributor would be for the Netherlands:
      J.F. McCaughin Division

      M. Argueso & Co., Inc.
      2628 River Ave.
      Rosemead, California 91770-3395