NEW! Slow Cool Glazes from Coyote.
Finally, there are crystal glazes without running, without seeding, and which you can fire along with your other glazes! The slow cool series currently consists of three crystal glazes, an aventurine glaze, and a beautiful iron red. By adding controlled cooling to a normal cone 6 firing, these glazes produce spectacular effects that were previously difficult to obtain.
HOW DO I DO THIS?
As the control panels for programmable kilns vary across brands, you should consult your owner's manual or contact the seller or manufacturer of the kiln for instructions on how to program your specific kiln.
Once you know how to program your kiln, enter the following schedule:
* 5 Ramps Total *
- 100℉/hr to 220℉ (this preheat ramp is optional)
- 350℉/hr to 2000℉
- 150℉/hr to 2200℉ hold 15 minutes
- 500℉/hr to 2150℉ hold for 15 minutes
- 125℉/hr to 1400℉
Thermocouples tend to vary slightly so you may need to tweak the top temperature for your kiln. Your witness cone 5 should be all the way down, and the witness cone six should be from halfway over to the tip even with the base (between cone 5 1/2 and 6), cone seven should be mostly straight.
WHY SLOW COOL?
These new glazes look their best when cooled slowly. Most modern electric kilns are less insulated than their gas fired counterparts, resulting in a quick cooling cycle that prevents many glazes from developing the richness they might otherwise have. Iron reds, crystaline glazes and others should be slow cooled to achieve their best effects.
WHAT WILL HAPPEN TO MY OTHER GLAZES?
By programming your automatic kiln to our recommended firing schedule many of your current glazes will look dramatically better. All of the Coyote glazes fall into one of three categories when slow cooled:
- WAY BETTER!!
- A little better
- Can't tell any difference.
We haven't found any glazes that look worse in a slow cool than they do in a regular firing.
WHICH OTHER COYOTE GLAZES LOOK GREAT IN A SLOW COOL FIRING?
Some of our favorites are Opal, Saturated Iron, Rhubarb, Eggplant, Mottled Blue, Rust Brown and Red Gold.
CAN I FIRE THESE NEW GLAZES IN A REGULAR FIRING?
Yes, the new glazes look fabulous in regular firings. A slow cool will maximize the growth of crystals and bring out the best in these glazes, but is not necessary to make them work well.
ARE THESE GLAZES FOOD SAFE?
Ivory Crystal, Crystal Celadon, and Crystal Lagoon will change color when exposed to acidic foods and are not recommended for food use. Autumn Spice, Mars Red Iron, Light Gold, and Summer Spice are suitable for food.
WHERE CAN I LEARN MORE ABOUT SLOW COOLING?
Mastering Cone 6 Glazes by John Hesselberth & Ron Roy was instrumental in introducing slow cooling to a wide audience. The slow cool schedule that we recommend is a modified version of the one found in this book.
If you are interested in learning how to mix your own glazes this is a great book, with a focus on making durable and attractive glazes, as well as some very nice recipes. It is still available as an ebook at masteringglazes.com
Basic Glazing Instructions
First you want to apply wax resist to the foot of your pot (where you don't want any glaze). When you dip your pot in bucket of glaze, the glaze won't stick where you have waxed. The glazes become molten glass in the kiln, so if there is any glaze on the bottom, your pot will stick to the shelf. This will wreck your pot and your kiln shelves! Paint a thin coat of wax on the bottom, as well as up the sides at least ¼ inch. All glazes move a little in the firing, and some are quite runny. Always leave enough room for your glaze to flow some without sticking to the kiln shelf. Until you are familiar with a particular glaze, it is better to leave some extra room.
- Use a thin coat of wax. It works better and dries faster.
- Let the wax dry for at least 15 or 20 minutes before dipping a pot in glaze.
- Use an old cruddy brush, they are never the same after using for wax.
- Clean your wax brush in warm water with a drop or two of dishwashing soap.
- Be careful not to get the wax where you don't want it, i.e. waxy fingerprints.
- Before you glaze your work, you should quickly rinse it under cold water.
- Thoroughly mix the glaze just before you use it.
To coat the whole piece in a single glaze, the easiest technique is to pick it up with a pair of glaze tongs, dip it in, count to three and pull it out. Make sure to empty it as you withdraw it. If you pull a bowl out still full of glaze it will weigh so much that the tongs will break through. Hold it upside down over the bucket to drain the excess glaze. There will probably be some glaze sticking to the waxed areas; wipe off what you can while you are holding it with the tongs. Set the piece down and let it dry. After it is dry enough to handle, turn it over and sponge off any glaze still remaining on the bottom. The foot must be perfectly clean before it can go in a kiln.
For brushing, most glazes need 2 to 3 coats. It is easier to get even coverage if you brush the first coat side to side, then the next coat up and down.
These glazes work best when fired between cone 5 and 6 (Orton Standard or Self-Supporting Cones, used as a witness cone placed on the kiln shelf during firing). If you use a kiln sitter you usually have to use a cone six in the sitter to achieve a good cone 5. For automatic kilns, we fire to cone 5 (fast) with a 15 minute hold. Every kiln is different, so you may have to fine tune your firing to achieve the best results.