The day before glazing day is waxing day. As I've mentioned before, I produce pottery like many potters, in cycles. First throwing, followed by trimming/altering, bisque firing, waxing, glazing and glaze firing. Yesterday was waxing day. Prior to being glazed, any area of a pot I don't want glazed receives a light coating of wax. When pots are dipped in the glaze buckets, the wax resists the coating. This is especially important for the bottoms of pots which will rest on the kiln shelf as if they were glazed the glaze would fuse the pot to the shelf. And a mug that's attached to a kiln shelf isn't very useful. Wax resist is also useful in decorating pottery by either leaving a portion unglazed or when putting a coat of a different color over a first layer and I want part of the first layer to not be covered.
I'm very grateful for our warming weather and sunny skies right now because it allows me to make use of several long sections of deck railing, as shown in this photo, to dry the waxed pots before moving to the next step of the process.