WHICH IS THE CORRECT PRODUCT FOR MY PROJECT?
RTV Silicone :
Casting Silicone :
Platinum Silicone :
Urethane Resin :
Polyester Resin :
Epoxy Resin :
Urethane Foam :
Urethane Rubber :
W.E.D Clay :
Buff Clay /
VS Tin Silicone
Ideal for molding sculpts/items which will be cast in a hard material such as resin, urethane rubber, urethane foam. Picks up minute detail and allows for multiple casts. RTV silicones are Tin based and mixed with a larger amount of part A to part B.
Ideal for facial prosthetics, full face masks/sleeves, creatures, body parts etc. Using a layered paint method allows for outstanding realism and the ability to hair punch individual hairs. Silicone is best cast from a polyester/epoxy or resin mold. Casting silicones include our Platsil Gel 00, Gel 10 etc range.
Platinum cure silicone, also called addition cure silicone, are two-component high tear strength and flexible mold or casting compounds. They provide a faster working time than Tin based RTV's such as our Platsil FS 20 range of molding silicone which cures in 30mins to an hour vs Tin based RTV's which cure 12 - 24 hours. Platinum based silicones are often 1:1 ration for easy mixing
Ideal for lightweight and durable rapid prototypes props, helmets, weapons, armour, filigree detail etc. Quick curing time (same day demold) Can be tinted with pigments and infused with metal powers. Typically on a 1:1 bases (view your products mixing ratios)
Ideal for mother molds over RTV silicone, lightweight molds for silicone casts and large hollow props such as rifles, helmets, set decoration where weight and strength are a concern. Is generally used by applying a gelcoat first to capture detail (be it mold or cast) and once tacky a laminating resin is applied along with fibreglass mat for strength (multiple layers) then finished with fibreglass tissue for a smooth inner or outer surface. Generally mixed on a ratio of 1 - 2% of catalyst to weight of based (resin). Check your products ratios.
Epoxy clear resin is used by hobbyists and professionals when creating clear pieces without a vacuum chamber, Standard Epoxy resins are used alot in the Marine world (Boats etc) and also as mother molds for silicone molds. They are more expensive than Polyester resins due to their faster cure times and reduced odour (but please note, while the smell won't be as bad as polyester resin, it is still as dangerous so be sure to take precautions. Requires fibreglass mat for strength.
Urethane Foams come in a wide assortment such as Hard/Rigid foam, soft foam, flexible foam, medium foam, gun foam etc. Hard foam is generally used for filling voids in castings to increase the strength of the finished resin piece while reducing weight (or even casting an entire piece but it would be fragile). Soft foams and medium foam are generally used for filling latex/silicone pieces voids or as direct casting for 'stunt' pieces with more specialised Gun Foams created uniquely for highly detailed props which will take a beating. All urethane foams self skin to a degree (Self skinning means a non porous finish to capture detail)
Urethane Rubbers come in a variety of shores like silicone (shore = hardness) and can be used on everything from creature suits and organic pieces (such as PT Flex 20) right through armor and weapons which need to be visually solid (and appear to be hard casts) but able to bend without breaking (such as PT Flex 70, 80 etc). In addition, they can be thickened with polyfibres for brush on applications.
W.E.D Clay (Walter E Disney Clay) is a clay designed to sculpt larger pieces (hands, heads, full size suits) in a cheaper and quicker fashion while still maintaining the workability of oil clay. WED clay is cheaper than oil based clays and sold in 25lbs bags and can be kept workable by sealing with a plastic bag and wet paper to keep the piece damp. When you wish to add more detail you can dry it with a hair dryer and you will notice the texture change to the point it can be worked like oil cay. Ideally you want to smooth over with 99% alcohol and not water.
Oil clays come in various types but the most well known are Chavant and Monster Makers. Oil clay is more expensive than WED but it does not dry out and is manipulated by heat and can be 'carved' more so than water based clays. Ideal for props with hard edges aswell as creature heads/hands, maquettes, miniatures etc.
Buff Clay / Water Clay is generally the cheapest clay and used to clay up your molds (as the clay will then be contaminated). It can be used to sculpt but be warned, it will dry and crack much faster than WED clay which contains oils to prevent fast drying times.
Casting latex is a simple to use material, simply pour in..let form a skin..pour out and repeat. Casting with latex requires a plaster mold for ideal use to pull latex casts and low humidity. Cheap but casts take longer than silicone, urethane etc. Latex inhibits alot of materials esp platinum silicone so do not use silicone in a mold that has held latex.
Plasters can be used as a cheap alternative to fibreglass or urethane resin for mother molds (be sure to use scrim to reinfoce) aswell as for casting initial lifecasts from an alginate mold. Plaster is also ideal for casting background pieces, set decoration, wall details in addition to a 'master' copy that may need to be reworked. Latex casting is also best done in a plaster mold
Tin (condensation) cured and Platinum ( addition) cured silicone rubber. Both types has advantages and disadvantages and neither are compatible with one another. Silicone rubber is an excellent choice for making molds, they offer excellent strength, flexibility, and are self-releasing. The only thing RTV silicone will stick to is silicone itself. Tin (condensation) cured silicone rubber uses tin salts as a catalyst and uses moisture in the air to transform from liquid to solid. Platinum (addition) cured silicone rubber uses a platinum catalyst and uses heat to transform from a liquid to a solid. Platinum (addition) cured silicone’s can be heat accelerated, for every 10 degrees above 70°F you can reduce the cure time in half, so if you heat the platinum cured silicone at 150°F it will be ready to use in 20-30 minutes.
Tin (Condensation) Cured
+ Typically less expensive
+ Less prone to inhibition
+ Will cure in lower temperatures or over frozen patterns
+ Excellent physical properties
– Not FDA compliant for food or skin applications
– Typically higher shrinkage compared to platinum cured silicones
– Over a long period of time can lose its flexibility and strength
Platinum (Addition) Cured
+ Very long library life
+ Some are FDA compliant for food and skin contact
+ Excellent physical properties
+ High heat deflection (can withstand heat -like the oven up to 400°F)
+ Can be heat accelerated
– Prone to inhibition caused by poisonous substrates such as sulfur, tin, synthetic rubber, some adhesives, latex, nitrile, etc..
– Requires very accurate and careful mixing