Liquid Rubber

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Smooth-On Urethane Rubber

New ReoFlex™ Series Urethane Rubbers

ReoFlex™ urethane rubbers are “next generation” products to our popular PMC-121 Series and offer superior physical and performance properties. ReoFlex™ urethanes are available in 20A, 30A, 40A, 50A and 60A Shore hardnesses and feature convenient one-to-one by volume mix ratios. Vacuum degassing is not necessary and ReoFlex™ rubbers cure with negligible shrinkage to a durable rubber that will last in production.

ReoFlex™ rubbers are available as either “wet” or “dry” consistencies. ReoFlex™ Wet cured rubber exudes an oil to aid in demolding concrete and gypsum plasters. It will enhance abrasion resistance and increase the production life of the mold. ReoFlex™ Dry cured rubber is dry and suitable for casting wax, gypsum and resins.

ReoFlex™ mold rubbers are used for a variety of applications including making molds to reproduce sculpture and architectural elements, as well as for making special effects, toys and prototypes. These rubbers will meet the stringent demands of production casting of wax, plasters, concrete and resins.

PMC-121 Series Liquid Rubber Compounds
Convenience * Performance * Versatility

Novice and master mold makers alike know the 1-2-1 series as the liquid rubber compounds that are easy to mix (1A to 1B by volume—scale not required) and easy to pour. The PMC-121 series addresses a variety of applications from mold making (for restoration, concrete casting, sculpture, etc.) to special effects to electrical encapsulation.

PMC-121/20 – added flexibility offers easier demold of pieces with undercuts.

PMC-121/30 WET & 121/30 DRY – very strong and durable for “soft” mold rubbers, 121/30 Wet has a built-in release agent that aids in the demold of plasters or concrete and helps extend mold life. 121/30 Dry is preferred by model makers & sculptors.

PMC-121/40 WET & 121/40 DRY – harder version of 121/40.  New high strength, high tear formula.

PMC-121/50 – contains a built-in release to aid in demold. offers good abrasion resistance and longevity for production casting of harder plasters (ultra-cal, hydra-cal) and concrete.

BRUSH-ON™ 40 “Brushable” Mold Rubber Compound

Brush-On™ 40 – a softer version of our popular Brush-On 50 with an ultimate shore hardness of 40A. Brush-On™ 40 is more pliable and flexible than BO 50 but still offers excellent abrasion resistance and high tear strength. It has the convenience of a one-to-one mix ratio and is easy to mix and apply with a brush or spatula. Brush-On™ 40 paints onto vertical surfaces and will cure with negligible shrinkage to a durable rubber that performs and lasts in production.

Brush-On™ 40 is compatible with BO 50. You can apply 2 layers of BO 40 and back it up with 2 layers of BO 50. Brush-On™ 40 is suitable for production casting of wax, concrete, hard plasters and other materials. It is used for architectural restoration, reproducing sculpture and many other applications.

Brush-On™  50 & 60 – developed to offer superior tear strength and abrasion resistance. They offera convenient one-to-one mix ratio by volume and give the user ample working time to apply the material – in the studio or right on the work site. With a creamy consistency, Brush-On™ 50 & 60 paint on easily to vertical surfaces. They will cure with negligible shrinkage to a durable rubber and will stand up to repeated casting of abrasive materials like concrete.

Brush-On 35 – a softer, more flexible version for fragile/intricate detail work.

Typical Brush-On Applications:

• On-Site Architectural Restorations
• Special Effects
• Casting Cement/Concrete
• Art Bronze Wax Molds

PMC-724 – by far the most versatile flexible mold compound available. It mixes and pours easily, curing to a durable rubber with negligible shrinkage. The low viscosity of PMC-724 ensures flawless pick-up of even the finest detail with minimal bubble entrapment.

PMC-724 PUTS YOU IN CONTROL! Using optional Part D, you can thicken PMC-724 to a paste-like consistency for vertical surface brush-on applications. If you like to work with a more flexible rubber, Part C is available to soften PMC-724 to lower durometers. A variety of colors and special effects can be achieved by adding color pigments, and for added project dimension, you can foam PMC-724. Color: Off-White.

Typical Applications

• Art Bronze Wax Molds (Lost Wax Process)
• Pre-cast Concrete Molds
• Fiberglass Panel & Part Molds
• Casting Urethane Resins and Epoxies
• Special Effects
• On-Site Architectural Restoration Molds

PMC-726 – offers all of the control and versatility of our popular PMC-724, but cures to an ultimate hardness of Shore A 60. It is ideal for casting chemically harsh materials (such as polyester and fiberglass – with use of PVA and release agent).

As with PMC-724, PMC-726 can be thickened for brushing on to available for vertical surfaces with optional Part D. Part C is softening PMC-726 to lower durometers.

Typical Applications:

• Architectural Reproduction
• Industrial Rollers
• Casting Resins (Fiberglass, Polyester, Urethane)
• Special Effects
• Casting Epoxies

PMC-744 – developed specifically for the Hobby/Ceramics field and the making of ceramic molds. Years were spent in research and testing. The result is a compound that is excellent for making molds that are strong, durable and dimensionally stable. Low viscosity ensures fine detail. PMC-744 will last longer in production than plaster and will not shrink like latex, saving you time and money. Color: Light Amber.

Typical Applications:

• Case Molds for Hobby/Ceramics
• Pre-Cast Concrete
• Plaster Block Molds
• Wax Candle Molds
• Special Effects
• Architectural Restoration
• Ornamental Plaster
• Mechanical Rubber Parts
• Casting Of A Variety Of Resins

PMC-746 – developed to make molds for casting gypsum plasters and like PMC-744, is particularly well suited for use as a case mold – especially large case molds where extra rigidity is required. Because of its durability and moisture resistant properties, PMC-746 is used by zoos and museums for a variety of molding, display/exhibit applications. Also, PMC-746 contains no mercury.

Typical Applications:

• Large Case Molds for Hobby/Ceramics
• Plaster Block Mold
• Pre-Cast Concrete
• Ornamental Plaster
• Special Effects
• Casting Smooth-On Rigid Polyurethanes and Epoxies

PMC-860 – new urethane rubber mold compound that has excellent performance properties. PMC-860 cures at room temperature with negligible shrinkage to a durable rubber that will last. It has good dimensional stability and exceptional abrasion resistance. It is ideal for production casting of concrete and hard plasters.

Typical Applications:

• Concrete Production Casting
• Plaster Block Molds
• Ornamental Concrete
• Concrete Stamping Pads

PMC-870 – offers strength, durability and wear resistance for repeated production use for those flexible mold applications that require a relatively hard rubber. PMC-870 is well-suited for a number of industrial applications including gaskets and pulleys, vibration and shock pads and production use with cements, hard plasters, fiberglass resins and epoxies.

Typical Applications:

• Concrete Molds
• Concrete Stamping Pads
• Gaskets for Industrial Equipment
• Industrial Rollers
• Vibration/Shock Pads
• Bushings and Diaphragms
• Pre-Cast Concrete
• Rubber Mechanical Parts

PMC-780 – designed to meet the most stringent requirements of industrial applications. PMC-780 is available in wet or dry versions and has become a standard among concrete casters because of its high tear strength and abrasion resistance. It is a very hard rubber that offers superior tear strength, tensile strength, impact and abrasion resistance. Because it is slightly harder than our 780, PMC-790 is often used to make concrete stamping molds. It is also used to make ball liners, foundry patterns and metal forming pads. You can’t get a tougher rubber anywhere!

Typical Applications

• Industrial Rollers and Belts
• Concrete Stamping Pads
• Rubber to Metal Bonding Applications
• Concrete Molds
• Ball Mill Liners
• Metal Forming Pads
• Casters and Impellers
• Foundry Patterns