About 25 years ago, I always mixed up my own earthenware slip. It is not difficult, just takes patience and some time and a strong back; however when I moved to the South, there were no sources (that I could find - this was before the internet) to buy the raw materials. The only slip available was in pre-mixed, 2 gallon boxes. The cost was considerably higher, but the convenience was nice.

Now, though it is getting more and more difficult to find local supplies for hobbyists in the area of casting ceramic molds. I recently spent two weeks trying to find a local source for a gallon of ready made porcelain slip to fill an order for one of my customers.

I was about to tear out my hair before I finally found a source in another state and I had to pay high shipping costs to just get one gallon sent to me.

During my quest, I did find a local source who would have provided me with all of the fixin’s to mix my own slip; however they did not have a recipe for porcelain casting slip, just porcelain clay.

While waiting for my gallon of slip to arrive, I began a quest to find recipes to mix my own slip. I’m thinking it won’t be too long before I’m going to have to mix my earthenware slip also. To that end, I decided to share with my readers what I find out. I did find one recipe for porcelain casting slip - fire range cone 6-10. I have not attempted to make it yet, so I can not vouch for its result. If anyone tries this before I do, I would love to hear back as to what they think of the final result.

I will also be adding recipes for other slips besides porcelain soon.

To see this porcelain slip recipe, click here

The look of airbrushing on ceramics is age old. You can see its early effects on pieces like the ones done by Hull Pottery. The subtle gradation of shading cannot be matched by any other technique. There is simply no way to effect the gradual shading of hues from one color to the next with a brush.

The most important step to airbrushing on ceramic bodies is in the preparation of the surface. It is important that there be a smooth dust-free surface before applying glaze or any other airbrushed paint. Whether the piece be slip cast or hand built, attention should be given to remove all blemishes, seam lines, joinings/attachments, and all imperfections prior to firing the greenware piece to bisque stage. After the firing, the piece should be dusted off with a stiff brush, removing any remaining particles in the crevices or on the surface and then finally wiped down with a damp lint free cloth. Allow the piece to dry thoroughly before beginning to paint it. Airbrushing with underglazes is best done on greenware unless you are airbrushing over a matte glaze.

It is a good idea to apply a base coat of paint or glaze over the entire surface. This creates a sound foundation for the other glazes to rest upon. This base coat will blend with additional colors during the firing process. It is suggested that there be a strong base of white or cream for light clay bodies (normal ceramic). For dark clay bodies, a brown or gray base works best (colored stoneware, terra cotta, etc). Do not apply heavy layers because they may shift during the firing process and your colors will run.

Paints need to be thinned slightly when using an airbrush and you may need additional coats to get the effect you are seeking. You may want to practice on a few small items to get a feel for the amount needed for a smooth surface on the finished item when using glazes. You want a smooth glass-like finish. Too thin and the surface with be rough, too thick and the colors will run.

You can airbrush underglazes, glazes and non-fired stains and create beautiful works of art. As with all techniques, practice makes perfect. Make notes and keep trying, you will find it well worth the effort.

To read more about air brushing click here