Process

Sketchbook

Claymaking

Throwing
Throwing Photos

Glazing
Glaze Recipes
Glaze Recipe Photos
Glazing Photos

Firing
Soda Kiln #1
Soda Kiln #2

Tools + Equipment
Treadle Wheel

Process: Glazing

Glazing is a vital part of the process, and one that some potters like more than others. To me, it's enjoyable when I know my glazes are working well, I have some new experiments to play with, and when I've allowed myself enough time to glaze for an upcoming firing comfortably. Otherwise, it can be fairly tedious and stressful. I can occasionally squeeze in time to take some photos along the way.

Following a preliminary bisque firing to cone 08, the pots are strong enough to withstand the handling required when glazing. The bisque also makes them porous, which lets the glaze soak into the clay, later forming the interface layer between the clay body and the fired glaze. I glaze by a combination of dipping and pouring, with the occasional use of brushes or a spray booth. I use cold wax to mask off feet and lid galleries, and occasionally use latex resist for decoration with multiple glazes on one pot.

During glazing I sort pots into groups based on which glaze they'll receive, then by size, which makes loading the kiln easier. When firing in gas reduction, I generally use anywhere from 5-10 glazes within a single firing of about 80 pots. For wood and salt/soda firing, I rely more on flashing slips and just a few liner or details glazes.

I try to make most of my glazing decisions prior to actually applying glaze. Once in the midst of the fray, it's easy to make bad decisions, and I need to save my attention for glaze thickness, application strategies, etc. Glazing is best when there is a rhythm to it, so I really like to get everything set up in advance to run smoothly.

The critical factors in the glazing process are properly mixed glaze batches and application thickness. Getting these two right requires precision and concentration; for me, a casual approach usually results in lower quality pots. I own a hydrometer, but don't rely on it yet, so the approach relies heavily on experience with each particular glaze and a lot of intuitive "feel".

While glaze recipes are easy to find in books, magazines and on the web, I've rarely found a recipe that works well right away. Even a very good starting recipe usually requires some fine tuning to adapt it to a particular clay body, raw materials, application methods and firing schedule. I never learned glaze calculation in school, and have yet to commit to a software package that would help, so I do it all by low-tech empirical testing. This is probably highly inefficient, and there are times where I wish I could troubleshoot a glaze more scientifically, but it works. I suppose I've gotten used to it, and that I want to retain some of the mystery of the way the materials interact. See my glaze recipes page for examples of some that I'm using currently.

I also do a lot of testing to modify existing batches (trying to improve certain properties, remove faults, or add new qualities) and some playing from scratch, looking for the accidental, unexpected or unique. I keep extensive notes of the clays, materials used, firing methods, etc., so that good results can be repeated later. I hang onto every clay tile that has unique information on it, resulting in boxes of hundreds of past experiments. They are a great place to start when trying to come up with a new glaze, or solve a problem with an existing one. (I've considered how great it would be to post all that information to this site, but also how much work it would take - maybe someday with a grant or an assistant!)