U.S. Gypsum TUFCAL 50 lbs. Bag

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TUFCAL 50 lbs.

Our Price: $21.50

Product Code: RMTUFCAL50

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Description

U.S. Gypsum TUF CAL� Plaster 50 lbs. Bag
TUF CAL is a polymer modified, high early strength, fibered plaster that has been specifically designed for all statuary applications where greater resiliency and chip resistance is desired. Can be slush cast as well as solid cast. Mechanical mixing is required for best results.
Please note: 100lb bags must be split and repackaged to be shipped UPS. Please expect an $18.00 Handling charge when ordering 100 lb bags shipped UPS.

�High early strength
�Excellent chip resistance
�Great for larger, hollow casts

Technical Properties                                                             English     Metric
Use Consistency (parts of water by weight per 100 parts plaster)        50         50
1 Hr. Compressive Strength                                                     2,000 psi     6.8 MN/m2
Dry Compressive Strength                                                       4,300 psi     29.6 MN/m2
Maximum Setting Expansion                                                        0.210%     0.210%
Density Wet                                                                         108.6 lb/ft3     1.74 g/cm3
Dry                                                                                     85.6 lb/ft3     1.37 g/cm3
Set Time*                                                                             27-37 min.     27-37 min.

General Directions and Guidelines
Preparing the Mix
Use potable water at temperatures between 70 and 100 �F (21 and 38 �C). Since variations in slurry (the plaster and water mixture) temperature produce variations in setting time, it is important to keep both the plaster and water in a stable temperature environment prior to use. The higher the temperature of the water, the shorter the set time.

Measuring
Weigh both the plaster and water for each mix. The water-to-plaster ratio is critical because it governs the strength
and the density of the final cast.

Soaking
Sift or strew the plaster into water slowly and evenly. Do not drop handfuls of plaster directly into the water. Allow
soaking for 1-2 minutes. The plaster should be fully dispersed in the water prior to mixing. Small batches require
less soaking than large batches. See bulletin IG503 for specific soaking instructions.

Mixing
Mixing the plaster slurry is one of the most important steps in producing plaster casts with maximum strength,
hardness, and other important properties.
Mechanically mixed plasters develop uniform casts with optimal strengths. Plasters can be mechanically mixed
through both batch and continuous processes. Proper blade and bucket dimensions are important for obtaining
the best batch mix.

Pouring
To prevent air entrainment and provide a uniform, smooth surface, careful pouring of the slurry is necessary. Agitation of the
filled mold is a further step used to prevent air at or near the surface of the cast piece. Whenever possible, the slurry should be
poured carefully in the deepest area so the slurry flows evenly across the surface of the mold.
Pouring a large amount of slurry directly on the face of the mold may result in slight densification of the cast at the point
where the slurry strikes the surface of the mold.

Drying
All plaster casts should be dried as quickly as is safely possible after manufacture so that maximum physical properties can
develop. Dry to a constant weight.
The best drying rooms or ovens provide (1) uniform and rapid circulation (minimum of 15-30 fps) of air with no �dead spots�
having little or no air movement, (2) equal temperatures throughout the entire area, and (3) provisions for exhausting a portion
of the air while replacing it with fresh air. High humidity surrounding the drying room or oven inhibits the efficiency of the drying
because the air pulled into the room is incapable of picking up much moisture from the molds.
The maximum temperature at which plaster casts are safe from calcination is 120 �F (49 �C).With substantial free water in the
cast piece higher drying temperatures can be used without difficulty.As drying progresses, the temperature must be reduced to prevent
calcination.The safe drying zone is in the shaded area of graph (below, right). Before removing casts from the dryer, the temperature
should approach that of the area around the dryer to prevent thermal shock.

Storage
Keep in a dry, stable environment indoors. Do not stack more than 2 pallets high. Keep from drafts. Rotate stock.