The answer to this question is not a simple yes or no. Microwaving clay can indeed harden it, but the amount of time required for this to happen will vary depending on the type of clay being microwaved.
Some clays will become hard enough to be used as a pottery material after just a few minutes in the microwave, while others may require up to 10 minutes or more.
Always be sure to test a small amount of clay first to see how long it takes to harden in the microwave before microwaving any larger quantities.
What Happens When You Microwave Polymer Clay?
- Microwaves cook food by creating movement in the fat, sugar and oil molecules, which produces heat.
- Polymer clays do not contain sugar or fat molecules, but they do have oil molecules. So if you place the clay in the microwave, a form of cooking will occur—but your creation won’t turn out the way you expect it to.
- Microwaves cook unevenly, which will leave some parts of your clay cured and other areas soft.
- What’s more, the areas of the clay that are cooking will receive all of the microwave’s electromagnetic waves, causing overheating.
- Overheating makes the clay bubble and can even burn it. Avoiding microwaves is crucial to safe crafting with polymer clays.
What About Softening Polymer Clay?
- Polymer clay, like butter, silly putty, and cookie dough, gets softer when warmed up.
- A microwave can be used to soften polymer clay, but there are limitations. If microwaved for too long, the clay will ignite.
- Sylvie Peraud suggests slicing the block of clay before microwaving for 10 seconds at a time.
- Another way to soften polymer clay is by immersing it in hot tap water for 10 minutes inside a ziploc bag.
Can You Boil Polymer Clay In The Microwave?
- Some people advocate using a microwave to boil water which contains the polymer clay, but this can lead to incomplete curing and weak items.
- The clay itself absorbs microwave energy and can still become superheated, even when submerged in water.
- For a quality and reproducible cure, use a calibrated oven.
Can You Microwave Modelling Clay?
- If the modelling clay is oil-based, it will melt when microwaved.
- If the modelling clay is made of polymer, it can burn and harden when microwaved.
- To be safe, only microwave modelling clay that is designed for microwaving and follow the manufacturer’s instructions.
Other Methods To Harden Clay:
- Water-based clay or air-dry clay does not require heating to harden them.
- The size of the sculpture will determine how long it takes for the project to fully harden.
- The best and most used method to harden clay at home is in the oven. Most clays can be placed in an oven at 275 degrees Fahrenheit for 15 minutes per quarter inch of thickness.
- You can microwave other materials that you may use in various crafting projects, such as glass, cardboard, or styrofoam.
