Table of Contents
What is the difference between Hydrocal and plaster of Paris?
Hydrocal is much stronger than plaster of paris. It also takes lots more detail, and most of all does not ‘slough off’ like plaster of paris. That is important for a long life scenery base. The sloughing of plaster results in lots of dust and chips on a continuous basis.
What is the difference between Hydrocal and Ultracal?
Ultracal 30 is more dense and harder than Hydrocal and is advertised by USG as a tool making plaster. Hydrocal is a casting plaster that hold detail well. Hydrocal is easier to work with post casting for corrections. Ultracal is more durable.
Is Hydrocal waterproof?
Hydrocal is waterproof. Aside from that, it is also weatherproof and scratch-resistant.
Can you carve Hydrocal?
GENERAL TIPS and TRICKS. Hydrocal is great stuff. Not only can we cast all this great stuff but I actually build most of my patterns with it, either using cast stocks like my own brick, stone or concrete, or hand scribing and carving all new originals in fresh Hydrocal.
What color is Hydrocal?
It is very white in color and exhibits setting expansion twice that of Moulding Plaster or Pottery Plaster.
How long does Hydrocal last?
It’s not the most cost-effective way to purchase Hydrocal, but it comes in a convenient, re-sealable container. When my last jar got down to the bottom, I discovered that, even in a closed jar, it has a shelf life of a year or two.
Does Hydrocal expand?
White Hydrocal is ideal for both solid and hollow casting of lamp bases, figurines, moldings and general castings. Offers long workability; setting expansion twice that of molding plaster and pottery plaster.
Is pottery plaster the same as plaster of Paris?
Pottery plaster is harder than Plaster of Paris. So, it is better for casting molds that experience wear and tear. However, Plaster of Paris is usually less expensive and is suitable for low wear and tear items. Also, some makes of Plaster of Paris are as strong as pottery plaster.
Is Hydrocal toxic?
CHRONIC: This material displays no specific toxic properties. INHALATION: Prolonged and repeated exposure to respirable crystalline silica can result in lung disease (i.e., silicosis) and/or lung cancer.
Is hydrostone heat resistant?
Ultracal 30 – Popular for mother molds, mask molds, prosthetic molds, and lifecasts that require resistance to heat. Hydrostone – Great for casting statuary and lifecasts such as hands. Very strong, even in thin cross sections. Fast setting stone material for casting production art pieces with good impact resistance.
Is Ultracal 30 waterproof?
Quick setting, dense white plaster in water resistant bag. Ideal for patterns, figurines, commercial casts, and sculpture. Ultracal 30 is 30% to 50% harder than casting plaster and works much like plaster in mixing, pouring, and setting.
How do you make a lightweight Hydrocal?
What is the mix ratio of Lightweight Hydrocal? The mix ratio of Lightweight Hydrocal is 5 parts Hydrocal to 2 parts water (1 1/4 cups Hydrocal to 1/2 cup water).
How do you mix USG Hydrocal?
Sift or strew HYDROCAL Brand White Gypsum Cement into water slowly and evenly. Do not drop handfuls of HYDROCAL Brand White Gypsum Cement directly into the water. Allow soaking for 1-2 minutes. HYDROCAL Brand White Gypsum Cement should be fully dispersed in the water prior to mixing.
What is lighter than plaster of Paris?
Alternatives include chalk and water, lime and water, soy powder and water, acrylic undercoat from the hardware store, matte medium or gelatin.
What is gypsum plaster?
Gypsum plaster is a white cementing material made by partial or complete dehydration of the mineral gypsum, commonly with special retarders or hardeners added. Applied in a plastic state (with water), it sets and hardens by chemical recombination of the gypsum with water. See also plaster of paris.
What is hydrostone plaster?
Hydrostone is a U.S. Gypsum product which is considerably harder than regular plaster of Paris, and lacks the period of plasticity in its setting curve which allows plaster to be worked directly. All plaster products should be mixed thoroughly, for at least two minutes.
What is gypsum cement?
Gypsum is a mineral and is hydrated calcium sulfate in chemical form. Gypsum plays a very important role in controlling the rate of hardening of the cement. Gypsum is added to control the “setting of cement”. If not added, the cement will set immediately after mixing of water leaving no time for concrete placing.
How do you cast with gypsum?
How to cast gypsum or plaster stone Add water to the bucket. Add plaster slowly until plaster stop absorbing water. Let it stay in bucket 5-10 min (do not mix) Mix carefully with hands and pour to the mold immediately. Shake mold from side to side to release an air pockets for face for the stone.
What is the compressive strength of plaster of Paris?
The horizontal compressive strength of the LPOP and CPOP are 1712 and 1595 N while the vertical compressive strengths are 1070 and 623 N, respectively.
What kind of plaster is used for pottery?
The most widely used plaster in the pottery studio is USG® No. 1 Pottery Plaster. This plaster is ideal for making slip-casting molds and other plaster castings where a high degree of water absorption is required. Pottery #1 requires 70 pounds of water to set up 100 pounds of dry plaster.
What is USG pottery plaster?
Pottery Plaster is a fine specialist plaster designed for use in casting of molds for ceramic products and plaster-craft replications. It is ideal for slip casting of sanitary ware and statuary, and for the manufacture of compression molds used in slab casting of tableware.
How hot does hydrostone get?
The maximum temperature at which USG Hydro-Stone Gypsum Cement molds are safe from calcination is 120 °F (49 °C). With substantial free water in the mold, a higher drying temperature can be used without difficulty.
How long does hydrostone take to dry?
One per mason jar. Then left it overnight, and it really brought some sponginess back to the buds. If used properly I’m sure you can get great results. So far, 10 hours in about a 1/2 oz does the trick.
How hard is hydrostone?
Hydrostone is considered the hardest and strongest plaster available. This material is 40 to 50 percent harder as compared to other casting plasters.
How strong is Ultracal 30?
Compressive Strength, Dry: 6500 psi (44.8 MPa) Density, Wet: 116 lbs./cu.
How long does Ultracal 30 take to set?
MIX RATIO: The manufacture recommended mix-ratio of Ultra Cal 30 is: 38 parts water to 100 parts Ultra Cal 30 by weight. The average setup time is 25-35 minutes when manually mixed.
