How to Sculpt Clay
Sculpting with clay is a fun hobby for everyone. If you want to learn how to sculpt clay like the pros, or even if you just want to brush up on your sculpting techniques, read our sculpting basics article. For more sculpting tips and sculpting tools and materials, see our other articles in this series.
Before you can learn how to sculpt clay on a technical level, you have to have an idea of what you are going to create. You needn't be especially artistic, and the image doesn't have to be anything intricate or even the entire picture. Have a sort of rough draft in mind (or on paper if you'd like) as a sort of reference to work from. Now that you have an idea, you can begin the modeling process. Start out just squeezing the clay in your hands to get a feel for the texture and to toughen it up a little. Next you can slowly manipulate the clay by pressing and pinching it with your fingers. The beauty of clay is that it can be reformed at any point and the whole project can begin again if necessary.
If you are working with ceramic clay, let base harden slightly after you have your rudimentary shape and before moving on to finer details (see more below). The next stage involves two opposite sculpting techniques: adding on and taking off. Don't be afraid to push pull and even totally remove off large chunks. Use your palms and fingertips to create subtle impressions, indentations, facial expressions and more. Grab a slab of clay and work it onto your main sculpture if you feel like it needs more girth or if you want to build up an area or feature. Remember, the beautiful thing about sculpting with clay is you can always start again. Fixing up faux pas is also really easy to do when you are sculpting with clay. When completed, polymer clay sculpting is placed in the oven to be cured at a low temperature. Different brands suggest different curing times and temperatures, but most will start somewhere around 260 degrees Fahrenheit and add 10-30 minutes per 1/4" of clay. Cured projects can be painted and finished.
An armature is a foundation usually made from mesh or wire that can be used to support delicate pieces of your sculpture or to bulk up a piece. Armatures do not work well with water-based clays, though, because the water evaporates during the curing process, and cracks as a result of caving into the ungiving armature. For more information on armatures, read our sculpting tools and preparations section.
Ceramic clay is different in that it dries out faster. When sculpting with clay ceramic, use a large block of clay and start shaping, scraping and modeling. As we said above, leave the basic shape to harden slightly (not too much), and continue sculpting with the easier to manage clay just a little while later. After you have your more honed shape, you can begin adding the smaller details, the textures and the additions that you may have worked on off surface (smaller detailed pieces such as hands or a face, are easier to work on separately and then added on later. Note: When adding on smaller additions, keep these pieces moist because thinner, smaller pieces will dry out faster than the rest of the larger sculpture.) Once all the sculpting, shaping and detailing is done, hollow out your sculpture from the bottom up. Leave approximately 1/2" all around as the wall of your sculpture. If certain pieces can't be accessed once put together, hollow out the pieces before attaching them to the main clay fixture. Ceramic clay is slowly dried out over several days using a bag to keep some moisture in, but letting some out as well. Move the bag further up the sculpture each day to allow more air to circulate, thus drying out the sculpture slowly and properly.
Here are a few terms and sculpting techniques that you may come across:
Under baking is a technique by which you cure the clay slowly at a low temperature for a long period of time. This process can result in a weak sculpture that breaks down over time. Over baking, on the other hand, is started at a lower temperature and left in for an hour at this temperature. With each hour, the temperature should be raised approximately 25 degrees. The clay becomes much darker than it would usually, though, so this method is generally only used for projects that are going to be painted or finished at a later stage.
Safety warning: ***When over baking, be sure to leave the clay in the oven until it has completely cooled. ***Over baking is also argued to be hazard to the eyes, throat and lungs because of possible hazardous gases that can be released in the process. Proper safety gear and precautions should be used at all times and especially with this method.