I have to admit, glazing is not my favorite part of the ceramic process. It’s probably because of its potential to make or break a good pot (and believe me, I have “broken” quite a few with poor glaze application). I tend to be a bit of a sloppy glazer and I sometimes rush through it a little more quickly than I should.
Denver, Colorado ceramic artist Annie Chrietzberg is the polar opposite of me in the glaze room: methodical and precise. I know my glazing outcomes could be greatly improved if I followed just a couple of Annie’s tips. So I am sharing them with the community in today’s post (an excerpt from our new free download How to Make Pottery: How to Learn Pottery Techniques and Enjoy Working with Clay). Hopefully you will benefit from Annie’s advice too! – Jennifer Harnetty, editor.
12 Tips for Ceramic Glazing Success
by Annie Chrietzberg
For complex forms consisting of thrown and textured elements, I use a combination of pouring, dipping and brushing to get the color where I want it. Dipping is the easiest way to ensure an even application, and pouring, with a little practice, is the next. Brushing takes more practice, time and attention, and I only use it when the first two methods are not options for a tricky place on a pot. The two troublemakers involved with glaze application are water and gravity. When a bisque pot becomes too saturated with water, it won’t accept glaze correctly, so use the least amount of water possible when glazing, including when you are making corrections. And as for gravity, I doubt there’s anyone who hasn’t experienced the wayward drip of one glaze marring the perfect application of the previous glaze.
This article was excerpted from the Tips from the Pros department of a back issue of Pottery Making Illustrated. To see more of what Pottery Making Illustrated has to offer, check out the latest issue here.
• Keep bisqueware clean. Lotions, or even the oils from your hands, can create resist spots where glaze adheres unevenly or not at all. Throughout all phases of the glazing process, including loading and unloading the kiln, handle bisqueware with a clean pair of disposable gloves. If you think your bisqueware has been compromised -- splashed with something, covered with grime, or maybe handled by a visitor -- bisque it again rather than risk a crawling glaze.
• Remove all dust before glazing including bisque dust, studio dust and even household or street dust. Use an air compressor for foolproof results, but work outside or in a well-ventilated area away from your primary workspace, as bisque dust is extremely abrasive to your lungs.
• Use silicon carbide paper to remove any rough spots you missed before bisque firing. Place your work on a piece of foam to prevent chipping. After sanding, wipe with a damp sponge to remove all traces of sanding dust. Use a damp sponge instead of rinsing, which should be kept to a minimum. Wring the sponge thoroughly and rotate it so each area is only used once. I tend to use half a dozen or so of those orange round synthetic sponges during any given glazing session.
• Glazes must be well mixed. I use an electric drill with a Jiffy Mixer attached. If there is dry glaze caked on the sides of the bucket, sieve the glaze, then return it to a clean bucket.
• Glaze all the interiors of your pots first by pouring the glaze in, then rolling it around for complete coverage. For complex pieces requiring a number of glazing steps, glaze the insides the day before to give you a drier surface to work with, especially for brushing.
• When removing unwanted glaze, scrape off as much of it as you can with a dental tool or a similar small metal scraper to keep a sharp line. A damp sponge removes the remaining glaze with a few strokes, keeping water usage to a minimum.
• Use a stiff brush to help clean glaze drips out of texture.
• For dipping glazes, select an appropriately sized container for the work at hand. I have lots of different sizes of shallow bowls that are perfect for dipping the sides of my pieces. Wide shallow bowls allow me to see what I’m doing, so I even use them for smaller things that fit into the glaze bucket.
• When you can’t dip or pour, it’s time for brushing. Watch your bisque as you brush—glaze is shiny and wet when first applied, then becomes matt as the bisque absorbs the water. If you recoat too soon over a damp coat, you’ll move the foundation layer rather than imparting a second coat. Consider gravity when brushing and hold the pot both to encourage the glaze to go where you want it to and to keep it from running where you don’t want it.
• If a drip flows onto a previously glazed surface, stop, set the pot down and wait. Resist the urge to wipe the drip with a sponge. Let the drip dry, then carefully scrape it off with a dental tool or metal rib. Use a small compact brush to wipe away glaze in areas you can’t reach with a sponge.
• Don’t brush glaze from the big glaze bucket. Pour a small amount into a cup, then briskly stir it occasionally to ensure that it stays properly mixed. Keep a large, damp sponge nearby to keep the brush handle clean. Stray drips often start with a handle full of glaze.
• If you’re glazing pots that don’t have a defined foot, push them across a piece of 220-grit silicon carbide sandpaper. The sandpaper removes some of the glaze from the contact areas, indicating where you need to wipe off the remaining glaze.
To see more images of Annie Chrietzberg's work, visit her website www.earthtoannie.com.