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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
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.
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
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
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
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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