What is Moulage used for?
Moulage is principally used for prosthetics for replacement limbs, fingers, etc. after ampu-tation. The material produces a good likeness.
In the sculpture field it is used extensively for face masks, relief molds, and body parts. Since the material is an alginate and can be used repeatedly, its expense is justified.
What is PosMoulage?
It is the positive casting material that can be used in conjunction with the mold ma-terial Moulage. It is a wax that can be brushed or poured into the moulage mold to create a positive cast. Microcrystalline Wax or any other wax can also be used in the same way.
The natural color of the PosMoulage is a main advantage of this material; the ease with which it can be brushed on is a second advantage.
What is the difference between Mold Rubber and Moulage?
Mold rubber is a latex base rubber that once exposed to air sets and cures and cannot be reused. It is an excellent material where multiple casts are required; the mold will give years of use. It can be stored and reused for casting for as long as 20 years.
Moulage is an alginate type of material used for quick body part casts. It can be stored for only short periods of time since it has to remain moist. An advantage of Moulage is that it is reusable and can be melted down after an initial mold and cast have been made. Moulage can be used to make molds of the face whereas latex cannot since it inhibits the breathing of the skin during the time it takes to set and dry.
Moulage is removed after a few minutes while it is still somewhat moist.
What is the difference between Mold Rubber and Casting Rubber?
Mold rubber is the material used to make the negative mold from which a cast will be drawn. Mold rubber is the negative. Casting rubber is the material that is poured or cast into a plaster mold and is the positive. It is used for dolls heads or hands. Casting rubber is the positive.
Is there silicone in White Rubber?
No. Silicone is a rubber specifically made of silicone. White rubber is not a silicone rub-ber.
What is the difference between positive and negative molds?
A negative is referred to as the mold since it creates a cavity into which material is poured to make a cast. The positive is the cast derived from the negative mold. The piece or model of which a reproduction is made is the positive and the mold made of the model for casting reproductions is the negative. Making a cast is positive; making a mold is negative no matter what mold making material is used.
What is a brush up mold?
A brush up mold is made of a thixotropic mold making material. Chemical components are mixed together to form a paste. The mixed material will have the consistency of mayon-naise and when set will be a flexible rubber.
The mixing proportions can be somewhat difficult to achieve and its use is not common among artists with average experience. It is a good material for making molds of ceiling or crown molding when remodeling older homes.
Can mold rubber pieces be used repeatedly?
When the mold rubber is cured after set-ting, it can be used to make about 100 simple casts of nonabrasive material such as casting
plaster. Abrasive material such as cement causes more rapid deterioration. When a posi-tive cast is made from casting rubber, the piece, once set and cured, cannot be re-used. Once either the positive or negative rubber has set it cannot be re-used.
Is Pliatex mold rubber flammable? Is it the same as latex?
Yes. Pliatex mold is latex rubber and yes, as with any rubber it is flammable but at very high temperatures of 600°F.
Can you get a Pliatex instruction book without getting the entire kit?
No. The instruction books are available with the kit or a more comprehensive book can be purchased separately by ordering Mold Making, Casting & Patina for the student sculptor by Bruner F. Barrie
Can you cast casting rubber into a latex mold?
No. The casting rubber to make a positive rubber cast can only be poured into a plaster mold. The plaster absorbs the moisture in the casting rubber leaving a solid surface that in essence becomes the cast when dry. If casting rubber were poured into a rubber mold of any type there would be no absorption and thus no drying or setting. The rubber would be self sealing.
Can you pour latex solid?
No. Latex mold rubber must be applied in thin coats, a layer at a time. Each coat must be thoroughly dry before the next coat is ap-plied.
What materials can you cast into latex rub-ber molds?
Only gypsum products (such as plaster and cement) can be cast into latex molds. The heat source from any other materials can distort
the interior surface of the mold and thus the cast. This does not always happen, but I can-not recommend anything other than gypsum products. Why take the chance? Once the mold is distorted, there is no fixing it.
Where do I get directions for mixing plaster, Moulage, etc.?
Mold Making, Casting & Patina for the student sculptor contains the required infor-mation. Mixing plaster is by water and powder proportionately. Instructions are usually on the container. The mixing proportions are approxi-mately one quart of water to five pounds of powder. Since so many types of molds can be made, all of which must conform to the speci-fications of the model, I suggest referring to the above mold making book. For bronze, vented, and gauged molds, Methods for MODERN SCULPTORS by Ron Young is suggested.
How does Bone Emulsion compare to Hy-drocal, Hydrostone, and Vatican Art Casting Stone for hardness?
Hydrocal and Hydrostone are natural gyp-sum products with their own tensile strength.
Vatican Art Casting Stone is a mixture of dif-ferent grades of gypsum and marble aggregate.
Bone Emulsion is a water-base mixture of hardening ingredients such as cornstarch, etc.
Adding Bone Emulsion to gypsum or moist clay enhances their strength but does not make regular casting quite so strong as Hydrocal. Of gypsum materials, casting plaster (now referred to as mould plaster, is the softest, followed by Hydrocal, Hydrostone, and finally Ultracal (the hardest) in degrees of hardness. Industrial grade gypsum is the strongest but is only used industrially due to its coarseness. Each material has its own specific use. Casting plaster can be used for molds and casts, Hydrocal should be used for casts and sometimes, if you are experienced, for molds. Hydrostone and the
harder casting materials should only be used for casting, not mold making.
What is the difference between Hydrostone and Vatican Art Casting Stone?
Hydrostone is a pure gypsum product with a low absorbency rate and high degree of hard-ness. Vatican Art Casting Stone is a mixture of several gypsum products and marble aggregate to produce a stone-like effect and hardness. It is still essentially a gypsum base product and should be treated as such, meaning it is not for outdoor use.
What is hot metal plaster and how is it differ-ent from casting plaster?
The thermal expansion and heat absorp-tion of hot metal plaster can withstand the high temperatures of molten metal such as lead and pewter, but not bronze. The mold (made from hot metal plaster) will not crack or explode when lower melting temperature metals are cast into it. Casting plaster will not withstand high temperatures and may crack or break if these materials are cast into this type of mold.
What are low temperature metals?
Lead is the first that comes to mind; pew-ter is also low melting but is a combination of lead and tin and is not that easy for the aver-age sculptor to cast. Lead isn’t that easy either since it has to be cast in one continuous flow or striations and layering will occur.
What are shims and which is better, aluminum or brass?
Shims are the separating pieces that mark the areas of a piece mold where the divisions are made to remove the mold for casting. They can be of clay, wood, metal, or other material that enables easy separation of the sections.
Most sculptors use brass or aluminum because
it is thin, flexible, and can easily be cut to con-form to the areas needing separation. A shim is generally not more than an 1½” in width since the mold walls will not be more than an inch or so thick. When the shim is placed in the model this inch is all that should be exposed since the plaster mold will only come to the top of the shim. Brass was used before aluminum but brass rusts when exposed to the water in the plaster, turns green, and can even corrode. Aluminum does not have these problems, so I suggest aluminum shims if you have a choice.
What is a Cesta bucket?
This bucket is a heavy impact rubber rein-forced with fiber glass strands making it one of the most durable mixing buckets available.