FormRub 65 Liquid Rubber

FormRub 65 Liquid Rubber is the firmest option (Shore A65) in the FormRub Series. Use this two-part, room temperature curing rubber to make durable molds for high-production casting and forming of concrete. Other common casting materials include plaster, wax, and, with proper release agents, some resins and foams.

The low viscosity and firmness of FormRub 65 make it ideal for casting larger parts where dimensional stability is required. Popular uses include texture and stamping mats, simple architectural panels, sound barriers, fences, pavers, slabs, patio stones and many other types of cast stone and GFRC.

FormRub 65 performs best for patterns and textures with minimal undercuts (e.g., slate, low-relief wood grain). For patterns/textures with deep undercuts, consider FormRub 35.

FormRub 65 offers a simple 1A:1B mix ratio and can be thickened with PolyFiber II for brush-on application.



Mix Ratio Shore Hardness Pour Time Cured Color Mixed Viscosity Specific Volume Demold Time
1A:1B A65 35 min. Hazy Yellow 1,500 cP 26.6 in³/lb ~16 hr.
Accessories: 74/75 Part C Softener74/75 Part X AcceleratorPolyFiber II Thickening AgentUV AdditiveTietex® FabricPoly Purge Aerosol Dry Gas


Product Literature: Technical Bulletin | Safety Data Sheets | Physical Properties Bulletin | Sealers & Release Agents Selection Guide


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