Which Type of Oven Thermometer Is Best When Baking Polymer Clay?

Oven-bake polymer clay is a fantastic way to create with your hands and express your imagination. Whether you’re a beginner hobbyist or a professional artist, you put valuable time and creative energy into your polymer clay masterpieces. But how can you be sure the finished product doesn’t end up underbaked or scorched when it comes out of the oven? Oven thermometers are an excellent way to test your oven’s temperature accuracy and ensure your creations become just as you’d imagined.

Why Is an Oven Thermometer Essential for Polymer-Clay Crafters?

Many ovens are inconsistent and inaccurate when it comes to temperature. Every oven is different, but you may have noticed that your oven has hot spots or takes longer to cure your clay than you expect. Monitoring temperature with a good oven thermometer is a must for polymer-clay crafters. 

For polymer clay to cure correctly, the oven temperature can’t be too high or too low. Most polymer clay is relatively resistant and won’t burn if your oven is a few degrees too hot. However, an overly hot oven can cause your creation to scorch, burn and release hydrogen chloride gas. On the flip side, baking polymer clay at too low a temperature will result in an underbaked, crumbly creation. 

After baking, polymer clay should cure evenly and turn hard. Most polymer clay products bake around 275 degrees Fahrenheit, with bake time depending on the thickness of the creation.

Can You Use an Oven Thermometer?

Oven thermometers offer an accurate, reliable means of measuring the temperature in your oven. Though ovens have built-in thermometers, these devices are often calibrated incorrectly or improperly located within the oven. Most ovens have hot spots, drafts and other sources of uneven heating, so unless you’re gauging the temperature in the middle of the oven where things bake, you may be reading the wrong temperature. The actual temperature of your oven may be off by up to 25 or even 50 degrees Fahrenheit — a significant difference when cooking certain foods and curing polymer clay. 

Most freestanding oven thermometers stand or clip easily on oven racks. You can move the oven thermometer around to identify hot spots and find the accurate temperature of your oven. You should aim to place the thermometer where things bake and where you can easily read it through the oven door. Constantly cracking the door to check your oven thermometer will leak heat and alter the oven’s temperature. 

To choose a good oven thermometer, look for options that are easy to read and place inside your oven. Models that are difficult to reposition or frequently slip around will add an unnecessary hassle to your baking. Accuracy, legibility, stability and ease of use are the most important factors in picking the right oven thermometer. 

How to Test Your Oven Thermometer

Before baking your polymer clay creations, it’s always a good idea to test the temperature of your oven. Run a pre-baking test to make sure your creations don’t scorch or break apart while curing. To test the temperature of your oven before baking, use the following steps:

  1. Pinch off a small portion of clay and form a disc about 1/4 inch thick and about 1/2 inch in diameter. 
  2. Find temperature and total baking time on the package instructions. 
  3. Bake the test piece.
  4. Remove the hardened test piece from the oven and check the color. Any darkened areas indicate that your oven is too hot. 
  5. If your oven is too hot, lower the temperature by about 10 degrees Fahrenheit and repeat the test. 

Oven Thermometer Best Practices

After running your pre-baking test, preheat your oven to the temperature indicated on the packaging. You can use your freestanding thermometer to run temperature checks, adjusting the oven as needed so it reaches and remains at the desired temperature. Take care not to exceed the recommended baking times and temperatures, and always use good ventilation while baking polymer clay. 

You can bake polymer clay on cookie sheets, glass surfaces or ceramic tiles. Some crafters prefer oven-safe work mats made of silicone. These products are washable, reusable and prevent you from having to move your creation from work surface to baking surface. Most kinds of polymer clay should be baked at 275 degrees Fahrenheit for 15 minutes per quarter-inch of thickness. For thicker pieces, you may consider initially baking for 15 minutes, then in additional five-minute intervals. The longer the clay bakes, the stronger the cure will be, but overbaking can cause bubbling and darkening.

Once your creation has finished baking, carefully remove it from the oven and allow it to cool. To test the clay’s curing, you can press a fingernail into the bottom of the piece after it has cooled. On a properly cured piece, your fingernail should leave a mark but not enter the clay.

Other Thermometer Options

If your oven seems consistently inaccurate and you’re having trouble finding a freestanding oven thermometer, there are other options available to you. As mentioned earlier, a good oven thermometer has several key features, including accuracy, readability, stability and the ability to reposition to different areas of your oven. You may be able to find some digital oven thermometers that offer these traits.

Digital options differ from traditional oven thermometers in appearance and functionality. Digital oven thermometers with a probe let you monitor the internal temperature of what’s cooking, such as a turkey or prime rib. Some thermometers have a metal problem attached directly to the digital display, while others feature a metal probe on a cord. Home cooks love the latter because they can leave the metal probe inside the oven while the digital display — placed on the counter or mounted to the oven door — gives the ongoing internal temperature of the food.

However, these digital oven thermometers work for baking polymer clay, too. Just leave the probe inside the oven, close the door, and read the digital display to measure your oven’s temperature accurately.

Another popular option for digital thermometers is the no-contact thermometer, which allows you to target a specific area with infrared lasers. This versatile tool has a wide temperature range and is easy to use when monitoring oven temperature: just point and shoot.

Shop Sculpey Polymer Clay Products

When you’re looking over your oven thermometer options for baking polymer clay, be sure to consider your oven-bake polymer clay products as well. Sculpey offers many clay types and color palettes to make it easy to express your imagination through clay. Shop Sculpey polymer clay products, and contact us today to start creating!

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