Kiln wash is an essential material used to ensure pots, sculptures and other clay-based objects come out of the kiln looking perfect. Knowing how to use and apply kiln wash is essential in achieving a good result, so in this article we will discuss where kiln wash goes as well as other important tips and considerations.
What is Kiln Wash?
Kiln wash is a special type of clay material that forms a protective layer for clay-based objects during the firing process. It prevents the surface of the clay from coming in contact with wire shelves, resulting in an even finish without any defects. Kiln wash is usually made from mixtures of calcined clays and other materials, such as alumina, silica and pyrophyllite.
Kiln wash is applied to the surface of the clay before firing, and should be applied in a thin, even layer. It is important to make sure that the kiln wash is completely dry before firing, as any moisture can cause the wash to bubble and crack during the firing process. After firing, the kiln wash can be easily removed with a damp sponge or cloth.
Preparing the Kiln for Kiln Wash
Before applying kiln wash, the kiln should be clean, free of debris and dust. Use a vacuum to get rid of any dirt inside the kiln. If there are certain stains, burn rough off using a torch. Make sure you wear protective gear (including an apron, goggles and gloves) when dealing with high temperatures inside the kiln.
Once the kiln is clean, you can begin to apply the kiln wash. Make sure to use a brush or sponge to evenly spread the kiln wash on the kiln walls. Allow the kiln wash to dry completely before firing the kiln. This will ensure that the kiln wash is properly adhered to the kiln walls.
Applying the Kiln Wash
Once the kiln is prepped, it’s time to apply the kiln wash. The easiest way to do this is by using a brush and a spray bottle filled with a mixture of 1 part water, 1 part kiln wash and a few drops of dish soap. First, spray the inside of the kiln with the mixture, starting with the inner walls and working your way around. Don’t forget to spray both sides of the shelves. Once all surfaces are lined with the mixture, use the brush to apply a thick coat of kiln wash. This will form a protective barrier between the clay pieces and wire shelves.
Allow the kiln wash to dry completely before firing the kiln. Once the kiln wash is dry, it’s important to check for any cracks or chips in the coating. If any are found, apply a second coat of kiln wash to ensure a complete seal. Once the kiln is ready, it’s time to fire up the kiln and start creating!
Curing the Kiln Wash
It’s important to let the kiln wash dry completely before firing. The best way to do this is by running a test firing at a low temperature – anything between 100 and 500⁰F (38 and 260⁰C). This will remove any remaining moisture from the kiln wash, as well as burn off any organic materials in the mixture. Once your kiln has cooled down, it’s ready for firing.
Tips for Using Kiln Wash
When buying kiln wash, make sure that you get the right kind for your project. For instance, if you’re working with porcelain, you’ll need a more refractory kiln wash than if you were using earthenware. It’s also important to wear a dust mask or respirator when applying kiln wash and during the test firing to ensure your safety.
Alternatives to Using Kiln Wash
If you don’t want to use a kiln wash, you can opt for other alternatives that provide similar results. You can use glass frit, which is available in liquid form or in granules. Another option is kiln cement – it’s made from a blend of refractory materials that protect pieces during firing.
Common Mistakes to Avoid When Using Kiln Wash
One of the most common mistakes people make when using kiln wash is applying too little. Make sure you use enough of the mixture to form a thick, continuous layer that covers all surfaces inside the kiln. If you don’t apply enough kiln wash, objects may stick to wire shelves during firing, resulting in unwanted blemishes.
Benefits of Using Kiln Wash
In addition to protecting your pieces during firing, there are several other benefits to using kiln wash: it ensures a consistent sheen on all of your fired pieces; makes it easier to clean your kiln after firing; and prevents staining or warping. It’s especially beneficial for high-fire processes since it helps prevent pieces from sticking or developing defects while in the kiln.
Knowing where and how to apply kiln wash can make all the difference when firing your clay-based pieces in the kiln. Now that you know what kiln wash is, how to prepare the kiln and apply it, how to cure it and other essential tips, you’re ready to get started on your project. Remember to always wear protective gear when dealing with heat.
