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Glaze Mixing Information

How To Mix A Glaze
Most recipes are measured by weight. It is standard to weigh a glaze out in grams using a triple beam balance. The following is a general guide to help decide what size bucket to use.
500 grams = quart
2,000 grams = gallon
5,000 grams = 2.5 gallon
10,000 grams = 5 gallon
1) Weigh out materials with a gram scale. Wear a respirator and gloves.
2) After each ingredient is weighed out, add dry materials to water. The amount of water will vary depending on the material and the desired thickness of glaze. You may mix chemicals together first and then add water to desired consistency if you prefer.
3) Blend
4) Put liquid mix through a 60 or 80 mesh sieve. Work the glaze through with a brush or your fingers. There is no need to push mixture through, too much pressure will wear out the screen.
5) Sieve again using the same screen or one with a smaller mesh. Screening glazes through multiple times will blend colorants together better.

If you have a glaze that settles, add 1-2% of a flocculant. Epson salts are a common flocculant. Dissolve in water before adding to glaze. If you need a stronger flocculant try a product called Flocs or Alsen & Combs Heavy Water. Use sparingly for Flocs. 1/4 teaspoon per gallon of glaze. For A & C Heavy Water the amount will vary due to glaze composition. Too much will turn glaze into a pudding. Readjust with water. Start with a 1/4 teaspoon per gallon and work your way up until desired suspension
People who are trailing or spraying glazes may prefer to deflocculate their glaze. It will keep the glaze liquefied and still in suspension using less water. Sodium Silicate and Soda Ash are common deflocculants and are often used in combination. Try about 1/4 - 1/2%.
Other common suspending agents are bentonite,Veegum Cer, and CMC. Veegum Cer also aids in the hardening of a raw glaze surface. Add 1-2% of bentonite to the dry mix before adding water. If you are using Veegum Cer, add a few ounces to a quart of water and mix well. Use this concentrated solution as needed to suspend your glazes. Careful, you probably need less than you think. For CMC, see mixing instructions below. If your glaze does not adhere to your work when glazed, try using gum arabic to help aid in this. It acts as a glue.


Instructions for mixing CMC
(synthetic gum)
Unlike natural gums, CMC will not deteriorate and does not need any preservative to prevent souring. Add the dry gum to water until small amounts of it float on the surface; repeat daily until the gum solution is the consistency of a cream or gelatin. The thickest consistency helps if you want raised engobes. If you are mixing with dry glaze ingredients or stains, start out using a small percentage of 1/4- 1/2 % of total weight and adjust accordingly to desired suspension.

Instructions for mixing Gum Arabic or Tragacanth Solutions
(natural gum)

Soak 25 grams of gum in 100 cubic centimeters of alcohol for 5 minutes. Make sure your container is dry and free from water before putting gum or alcohol in it. Stir for 5 minutes. Grains will lose some of the sharp edges. At this point, add water and stir vigorously. These natural gums should reach a consistency of custard or molasses. This will make approximately 1/3 gallon of solution. Note: since these are natural gums and will deteriorate quickly, add 8-10 drops of oil of cloves to prevent souring.


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