Pottery plaster is important both ingredient and a working mold medium. From whiteware and sanitaryware to artware and statuary, from insulators and stoneware to special refractories, the versatility of gypsum is a valued resource. Without gypsum to shape and dewater the clay, slipcasting, jiggering and pressing operations would not be nearly as effective. To a lesser degree, the same could be said for our tooling plasters used in models, case molds and block molds – its secondary application. For more information, contact us today at 1-800-695-6367, or find a sales contact in your area.
Georgia-Pacific pottery plasters have a consistency that allows high-density molds to be produced, then poured without pinholes or loss of detail. Uniform, moderate expansion characteristics mean proper release. There is no binding or warping. You are ensured proper fit on a jigger ring, and you can count on an accurate size and shape.
Thanks to the extended, consistent plasticity period of our pottery plasters, you also enjoy excellent workability. Mold variations are kept to a minimum. The dimensional stability resists abuse, prolongs usefulness, and promotes uniform water absorption.
Whether you are concerned with purity, absorption or set time; mold life or strength - or any combination - there is a Georgia-Pacific pottery plaster to fill your need. Chances are one of our industrial plaster products features the exact formulation that meets your requirements. If not, we will gladly customize a special formulation based on your specifications.
When trouble is experienced, the mold shop foreman should examine the problem to see which of the above conditions are being ignored. The best procedure is, of course, to see that the rules are not violated in the first place.
Mold strength, hardness, absorption and density are developed to a maximum during the mixing process. At this time, gypsum particles are dispersed in water and all air is removed from the resulting mixture.
Two different methods can be used. One is continuous mixing, a process by which custom-engineered equipment automatically meters and mixes exact proportions of plaster and water. In continuous mixing, the ingredients are blended together at high velocity, instantly forming a slurry without the need for soaking. The resulting mixture is then pumped through a hose to the point of use.
So that a mold's physical properties can develop to the maximum level, the mold should be dried as quickly, thoroughly and safely as possible. Drying is the evaporation of "free" water from the mold which can be either a natural or forced air process. When the center of the piece reaches the temperature of the air surrounding it, drying is complete.
For important product fire, safety, and use information, go to gp.com/safetyinfo.
MSDS: #42A Gypsum Plasters (85KB/6pgs)
Fiche Signalétique: #42A Plâtres Industriels (66KB/6pgs)
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