Can You Make Your Own Clay For Pottery?
Making your own pottery clay at home can be a fun and rewarding experience for both beginner and expert potters alike. The ability to customize and control your clay’s ingredients and properties gives you greater creative freedom when handbuilding or throwing on the wheel. However, formulating the perfect homemade clay does require some trial and error. It may take testing of different clay recipes and techniques before you produce a clay that has the right workability, durability, firing characteristics, and aesthetic qualities for your needs.
The primary benefits of making your own pottery clay are full customization and independence from clay suppliers. You can experiment with local, natural materials you may have on hand. This allows you to create clay suited for your skill level, intended uses, and artistic vision. However, crafting good clay from scratch does involve effort in sourcing, formulating, testing, and refining recipes. Without proper instruction or experience, your initial homemade clay attempts may prove too fragile, prone to cracking and breakage. Proper drying, firing, and glazing is also key to creating finished pottery pieces that will hold up to their intended use.
Types of Clay
There are three main types of clay used for pottery and ceramics – earthenware, stoneware, and porcelain. Each type has different properties that affect its suitability for certain projects.
Earthenware is a low-fire clay that is porous when fired. It can be fired at lower temperatures around 1800°F. Earthenware has a coarse texture and absorbs water easily, making it less durable than stoneware or porcelain. It comes in natural earth tones like red, brown, and terracotta. Earthenware works well for items like flower pots, decorative pieces, and tiles.
Stoneware is dense, vitrified clay that becomes non-porous when fired at high temperatures between 2100°F – 2300°F. The high heat makes stoneware very durable and watertight. Stoneware has a finer texture than earthenware, and resists chipping and cracking. It can be left unglazed or finished with colorful glazes. Stoneware is often used for tableware, large pots, and other functional items.
Porcelain is a white, translucent clay made from kaolin. It fires at very high temperatures up to 2330°F. Porcelain is highly vitrified, non-porous, and very strong compared to other clays. It has a fine, smooth texture that allows for delicate detailing. Porcelain is commonly used for tableware, sculptures, tiles, and other decorative items.
Clay Ingredients
The main ingredients needed to make homemade clay are:
- Clay – This provides the plasticity and binding properties. The type of clay determines the clay body characteristics and firing temperature.
- Sand – This is added as a filler to reduce shrinkage and cracking. Sand particles help reinforce the clay body.
- Grog – Crushed, prefired clay or ceramic material added as filler. Grog opens the clay body for improved moisture absorption and
reduces shrinkage.
The proportions of each ingredient determine the clay body properties. More grog/sand makes clay more open with less shrinkage, while more clay increases plasticity and strength. Knowing the role of each ingredient allows controlling clay characteristics.
Sourcing Clay
When making your own clay at home, you’ll need to source the raw materials. Here are some options for finding or purchasing clay:
Digging natural clay – One way to source clay is to dig it yourself. Certain regions have natural clay deposits, often near rivers, lakes, or other water sources. Do research to identify clay digging sites in your area. You’ll need to obtain permission from landowners before digging on private property.
Purchasing clay materials – For most home potters, it’s easier to purchase clay ingredients. Craft stores sell clay products like powdered clay, bentonite, and porcelain. You can also find materials online. Make sure any clay is marked as safe for firing/pottery. Pure clay types like kaolin or red art clay work best.
When buying clay, aim for a high level of purity without additives. Some “pottery clays” have extenders that may affect firing. For full control over ingredients, get materials like kaolin or bentonite clay in their raw powdered form.
Clay Recipes
When making your own clay at home, the ingredients and their ratios are key to creating a clay body with the desired characteristics. Here are some example recipes for different types of homemade clay:
Simple Air-Dry Clay
This is an easy clay that air dries at room temperature and doesn’t require firing.
- 1 cup flour
- 1 cup salt
- 1/2 cup water
Mix the flour and salt together, then gradually add the water while mixing until a dough consistency. Knead for a few minutes until smooth. The clay is ready to use.
Oven-Bake Clay
This clay recipe can be hardened in a regular kitchen oven, no kiln required.
- 2 cups baking soda
- 1 cup corn starch
- 1 1/4 cups water
Mix the dry ingredients first, then add the water bit by bit and knead into a smooth dough. Bake clay creations at 300°F for 15-20 minutes to harden.
Low-Fire Clay
This clay body can be fired at lower temperatures around cone 06.
- 25% kaolin
- 25% ball clay
- 25% fire clay
- 25% silica sand
Measure out the dry ingredients by weight in the specified ratios. Mix together thoroughly then add water a little at a time until a workable consistency is reached. Allow to sit overnight before using.
Mixing & Preparing Clay
Properly mixing and preparing your homemade clay is crucial for achieving the right consistency for working with it. Here are some key steps:
Mixing the Clay
Start by combining all of your dry ingredients in a large bucket or plastic tub. Use your hands or a trowel to mix everything together thoroughly. Make sure there are no dry lumps or pockets of a single material.
Next, slowly add water while continuing to mix. Add just enough water so the clay forms into a smooth, cohesive ball. The clay should be moist but not dripping wet. Too much water will make weak clay that cracks and flops over.
Wedging the Clay
Once mixed, the clay must be wedged to remove air pockets and evenly distribute moisture. This is done by cutting the clay into chunks and then slamming and folding the chunks together on a wedging table over and over. Do this until the clay has a uniform color and plasticity.
Wedging clay takes some practice. Apply even pressure as you fold to avoid trapping air bubbles. Cutting and slamming helps align the clay particles. Work any dried bits back into the mass. Well wedged clay should be smooth, elastic, and lump free.
If the clay is too wet, let it sit uncovered to dry slightly. If too dry, mist with water and wedge to incorporate. The perfect consistency is cool, smooth, and pliable like playdough. Once wedged, cover the clay in plastic wrap or an airtight bag.
Testing Clay
After you have mixed and prepared your clay, you’ll want to test it to ensure it has the proper properties for pottery-making before committing to a project. Here are some key ways to test your finished clay:
Plasticity
Knead a piece of clay in your hands to get a feel for its plasticity – how smooth it is, how easily it takes shape, and whether it cracks at all when manipulated. Good pottery clay should be smooth, pliable, and not prone to cracking. If your clay is too wet and sticky, let it dry out more. If it’s too brittle, consider adding a small amount of water.
Strength
Form a piece of clay into a snake shape, then hold it horizontally by both ends and gently bend it into an arc. Clay that will hold its shape has good strength. If it droops or snaps, it may be too wet or too brittle. Let it dry more or add a small amount of water or binder like vegetable oil.
Test Tile
Form a small flat square tile out of clay, let it dry, then fire it in a kiln or oven according to your clay recipe’s instructions. Examine the test tile – it should be hard and durable without cracks. Cracking means the clay needs more binder, drying time, or a slower firing schedule.
Testing your clay thoroughly will help identify any issues with plasticity, strength, or firing before you begin a project. Adjust recipes and preparation as needed until your clay performs how you need it to for pottery work.
Storing Clay
Proper storage is crucial for maintaining the ideal moisture content and consistency of homemade clay. Here are some tips for storing clay:
Wrap clay in plastic and squeeze out any air pockets to prevent drying out. Store in an airtight container like a plastic bin or ziplock bag. Adding a damp paper towel helps regulate moisture.
For long term storage, cover clay in plastic wrap then a layer of damp newspaper before sealing in an airtight container. The newspaper will absorb excess moisture. Check periodically and remoisten newspaper as needed.
Store clay in a cool area around 60-70°F. Avoid temperature fluctuations that can cause drying and cracking. Freezing is okay for raw clay but can damage finished pieces.
Knead a bit of vegetable oil into clay before storing for an extended time. This helps prevent drying and makes reconstituting easier.
Mark storage containers with the clay type and date. Use oldest clay first when possible. Discard if smelling bad or growing mold.
With proper storage techniques, homemade clay can last for several months up to a year before needing to be reconditioned or discarded.
Working with Homemade Clay
Tips for using homemade clay for pottery projects:
Here are some tips to help you successfully work with clay you’ve made at home:
– Knead the clay well before using to remove any air bubbles. Homemade clay can be sticky at first, so kneading it thoroughly will make it smoother and easier to work with.
– Let your clay age for a few days or up to a week after mixing. This allows the ingredients to fully integrate and the clay to firm up. Aged clay is much easier to handle.
– Keep your clay moist and store it in an airtight container or plastic bag. Add a damp paper towel to the storage container to maintain moisture. Dry clay can be reconditioned by mixing in some water.
– Homemade clay is quite soft, so don’t try to make large or thin projects that require a lot of structural support. Small bowls, cups, beads, and ornaments work well.
– Let your finished clay pieces air dry slowly, then fire in a kiln according to clay instructions. Firing helps harden and strengthen the clay.
– Consider adding acrylic fortifier or cornstarch to homemade clay to improve its workability, durability and quality after firing.
– Be patient when working with homemade clay! It requires more care than manufactured clay but allows you to create unique pottery from scratch.
Conclusion
Making your own clay can be a rewarding do-it-yourself project for potters, allowing you to create a clay body customized to your needs. The process involves sourcing clay materials like powdered clay, sand, and organic additives, then mixing them together with water using simple kitchen tools. Recipes can be found online, but testing is crucial to achieve the desired plasticity, workability, firing characteristics, and color. While homemade clay takes more effort upfront, the ability to control the clay properties and avoid contaminants makes it worthwhile for many potters. The experience also builds knowledge and a deeper connection with the clay medium. As long as you use care in preparation, storage, and firing, homemade clay can produce pottery just as viable as commercial options. Though buying clay is easier, creating your own is accessible for any potter willing to experiment and learn.
