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.
The following tips may help you as you work with your glazing and airbrushing
a) Avoid handling the piece once you have it ready to paint
b) Donít use hand lotions while handling the art items as finger prints can prevent the glaze or paints from adhering to the surface of your item, thereby creating thin or bare spots.
c) Once a piece is airbrushed, avoid touching the painted surface. Your fingers can actually lift the thin layers of glaze and paint off your item. This will seriously ruin the shading desired by the technique. There are special tongs with teeth that can aid in moving your item from table to kiln with no damage. Otherwise, be creative and do everything possible to prevent touching the surface with fingers or other items that may smudge the paint.
d) Thick glazes are not suitable, glazes need to be of cream consistency. Most airbrushes with jars and single action have large enough orifices to accommodate spraying cream consistency glazes.
e) Where possible, begin spraying your item off the piece then move the airbrush to your item while it is spraying to prevent blotches of color from sudden blast.