Pottery throwing is an art form that has been beloved for centuries. It’s a process of shaping clay into useful or decorative objects on a potter’s wheel. But before beginning, it’s important to wedge clay correctly; otherwise, it can lead to cracks, weak pottery and other common problems. In this article, we’ll explain why wedging is essential, provide some tips to do it right and discuss how to store clay that has been prepped for throwing.
What is the Purpose of Wedging Clay?
Wedging clay is a kneading process that aligns the molecules in the clay. When you wedge clay, you’re actively eliminating air pockets, preventing moisture loss and helping the clay keep its shape better when thrown on the wheel. The process also removes any rocks or other items that may have become lodged in the clay as you mix it.
Wedging consolidates the clay into a form that sets it free for your creativity to take hold. For example, handbuilding techniques such as pinching don’t require wedging since you are forming the clay with your hands But when throwing on a wheel, wedging sets up pieces of clay to be properly formed.
Techniques for Wedging Clay
The goal of wedging is to bind clay particles together. Typically, this is done by pushing down and twisting the clay in a figure eight motion. You can also use your knuckles when wedging to make sure all air bubbles are removed. It’s important to be gentle with your clay and not to overdo it – wedging too much can make it too wet, leading to lack of stability during throwing.
It’s also helpful to store your conditioned clay in a plastic bag, so it won’t dry out before you use it. To help the clay retain moisture, wrap it in something that will prevent evaporation, like a plastic zip top bag or damp towel.
Benefits of Wedging Clay
Wedging your clay correctly has many benefits. The process eliminates trapped air bubbles, which can cause pieces of pottery to be uneven or crack upon impact when fired. Wedging also prevents moisture loss so that you can be sure that your clay is just the right consistency to throw on the wheel.
Wedging is also beneficial for efficiency; when you wedge and condense your clay before you throw, you spend less time adjusting as you move from step to step of the pottery wheel process. Lastly, it reduces waste as it allows you to get more use out of the same chunk of clay.
How to Avoid Common Mistakes When Wedging Clay
When wedging, it’s important not to wedge too much – doing so will make the clay too wet and unstable on the wheel. Also, ensure that you evenly spread moisture and pressure evenly throughout the clay when wedging. If not, there could be inconsistencies and weak parts that cause pieces to break easily when fired.
To avoid overworking your clay, watch for signs of watery sogginess and feel for tiny air pockets as you wedge. You may not even need to add more moisture; if so, simply reduce the pressure to help loosen up trapped air bubble particles as you work.
The Right Amount of Water to Add During Wedging
Adding water to your clay during the wedging process helps release trapped air and makes wedging easier. The right amount of water plus time and movement results in more pliable and durable clay achieved quickly. Depending on the type of clay you’re using, anywhere between 10 and 15% water will help soften while not making the clay too wet or sticky.
When adding water, start with a teaspoon at a time until you reach the desired consistency and texture. Remember, you can always add more water if needed; adding too much at once can make the clay difficult to work with.
Common Problems that Occur When Not Wedging Clay
Not wedging clay correctly can lead to a variety of problems. Air pockets in the clay can cause pieces of pottery to crack or collapse when fired in the kiln. Unwedged clay can also lead to uneven walls or body warping due to trapped moisture during throwing.
Furthermore, not wedging can increase production time due to constantly having to adjust during the forming process. The right amount of wedging ensures that your base shapes come out consistent on each piece and your pieces fire true every time.
The Best Ways to Store Wedged Clay
Once you wedge your clay, it’s important to store it properly so that it doesn’t dry out. Wedged clay is best stored in plastic zip top bags in a cool, dry place.
Wrapping your bags tightly will help keep your clay from cracking or shrinking unexpectedly due to changes in temperature or humidity. It’s also advantageous to store them in Tupperware containers as they create an airtight seal and don’t allow any air moisture to travel in or out.
Tips to Make Throwing Easier After Wedging Clay
After wedging and conditioning, your clay should be ready for throwing. Here are some tips to help make the process easier:
- Work quickly – wetter clay dries out quickly, so act fast and keep a wet cloth handy.
- To save time and energy while working on multiple pieces of pottery, center each piece one at a time.
Using powerful but gentle motions when throwing can help keep your pieces symmetrical. Lastly, make sure your hands are oiled with a thin layer of Vaseline or another preferred substance before touching the wet clay – this will prevent sticking.
Conclusion
Wedging clay is an essential step in pottery throwing that is often overlooked but should not be taken lightly. Not only does it make your throwing process easier, but it also prevents common problems like uneven pieces or cracking during kiln firing.
When done correctly, wedging eliminates issues and allows you to achieve desired shapes with ease. It also helps conserve resources as well as moisture within the clay since excess moisture can be absorbed as clay continues to be used over time. By following these guidelines for wedging before throwing, for ensuring proper storage, and for proper techniques on the wheel, any potter can achieve beautiful pieces that last for decades.
