Buzz
There are various types of clay for sculpting, including polymer clay and air-dry clay, which are commonly used to create interesting items such as bowls, jewelry, and other crafts. You can easily finish your creation by baking polymer clay in an oven or air-drying the clay.
Steps
Bake Polymer Clay
Use a needle to create an air hole if your model has air pockets. For models with internal air pockets, you need to create a hole to prevent cracking due to temperature changes in the oven. Use a needle to poke the model until it punctures the air pocket inside.
- If there are no air pockets in your model, you don't need to worry about creating an air hole!
- Be sure to poke at least one hole for each air pocket to allow the air to escape.
- For example, many animal models are hollowed out inside to keep them lightweight. Also, jewelry pieces like earrings can have air pockets, especially delicate items.
Note that some types of clay, such as oil-based clay, are not intended to harden. Therefore, be sure to check the packaging of the clay you are using to confirm!
Read the instructions on the packaging to determine the baking temperature. Most clay products come with instructions that specify the baking temperature, usually ranging from 100 to 150°C. Check the packaging to see if the temperature varies based on the thickness of your model, then preheat the oven to that temperature.
- If using multiple types of clay from different brands in one model, follow the instructions for the clay that makes up the majority of the model. If unsure, set the temperature to around 129°C.
Place your clay model on a ceramic baking tray. While the oven is heating up, place your clay model on a ceramic piece suitable for baking. You can use a ceramic baking dish, or even a ceramic tile.
- Ceramic material retains heat well and helps prevent sudden temperature fluctuations when opening the oven door.
- Avoid using metal or glass trays, as these materials are more prone to temperature changes.
- Do not use a tray that is also used for food, as polymer clay contains pigments and other chemicals.
Bake your clay model immediately after painting or glazing. One advantage of polymer clay is that you don't need to wait for the paint to dry before baking. Once you've finished applying 1-2 layers of paint, preheat the oven and get ready to bake.
- Models that are painted or glazed will require a slightly longer baking time. Generally, each additional coat of paint or glaze will add 3-5 extra minutes to the baking time.
Bake the clay according to the time specified on the packaging. Most clay brands recommend a baking time between 10-30 minutes, depending on the thickness and color of the clay. The general rule is to bake according to the time on the packaging for every 0.65 cm of thickness.
- For example, if your model is 1.3 cm thick and the packaging suggests baking for 15 minutes, you should bake it for 30 minutes.
- If you've lost the packaging, it's best to bake at a lower temperature for a longer time (such as 30-40 minutes) to be safe.
Prepare an ice water bath while baking the clay. Choose a large pot or bucket that fits your model. Fill it with ice water, leaving about 5 cm of space from the top to allow for water displacement.
- The model should be completely submerged in water, so it's best to use the largest pot you can find.
Remove the model from the oven and immediately submerge it in the water. Once the baking time is over, use a spatula to take the model out of the ceramic tray. Carefully transfer the model into the ice water bath and let it soak for at least 30 minutes to prevent the clay from overbaking. Use your hands or tongs to remove the model once it has soaked long enough.
- Right after baking, the model may be slightly soft on the outside, so tools like tongs could leave indentations on the hot clay surface. Only use tongs to remove the model from the ice water, not to submerge it.
- If you're unsure how to submerge the model, you can just place the entire ceramic tray into the water.
Air-dry Clay
Let the clay model air-dry for 24-48 hours. Place the model in a dry, well-ventilated area and avoid handling it. Check every 4-6 hours to ensure it isn't cracking or breaking and to confirm it's hardening. Drying times will vary depending on the model's thickness and the air's humidity, but most air-dry clays will fully dry within 72 hours.
- If your model isn't hardening after about 12 hours, try increasing the temperature by using a hair dryer to blow air on it or place it in the oven at the lowest setting for 1-2 hours. Be sure to check periodically.
Fix cracks that appear during drying. As the clay dries, you may notice some cracks or indentations that weren't there before. To smooth these cracks, dip your finger in clean water and gently smooth over the imperfections a few times.
- If large cracks form during drying, you may need to remake the model by kneading the clay again. Add a bit of water to the clay, wrap it in a plastic bag for about 10 minutes, then knead it again, adding small amounts of water until it's soft enough to sculpt.
Flip the model after 12-24 hours of drying. If your clay model has multiple sides, such as a pot or jewelry, flip it over to allow the bottom to dry. This should be done halfway through the drying time, depending on the type of clay you're using.
- Be very careful when handling the clay. Try not to touch it more than necessary.
Wait for the clay to dry before painting. Adding color or details to the clay is easy. Simply wait for the clay to dry and then apply acrylic or tempera paint using a brush. Allow the paint to dry for 24 hours, then spray a protective coat over the entire surface of the clay.
- For example, if you're creating intricate patterns on a clay teapot, be sure to use a small, fine brush, and spray a protective coat over the teapot once the paint is dry.
Tips
- When baking clay, try to avoid opening the oven door to prevent heat loss or cracking caused by sudden temperature changes.
- Be patient! Some types of clay may take up to 72 hours to fully dry. Your item could be damaged if you touch or move it before this time.
- Ensure you work in a well-ventilated area when baking clay.
