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TAP Urethane RTV Mold-Making System


RTV: Room Temperature Vulcanizing
Urethane RTV is a two-part system that cures a flexible and high strength Shore-A 30 mold rubber (for comparison purposes, household silicone sealant is approximately Shore-30). Excellent tear resistance is another benefit of Urethane, yet it is easy to cut for two-piece molds. Urethane is an easy-releasing rubber for casting gypsum plasters and waxes without release agents and is excellent for casting cement, epoxy, polyester, or Urethane with proper release agents.
  • simple 1 to 1 mix ratios
  • low viscosity (flows easily)
  • excellent detail, flexibility, and durability
  • maximum recommended casting temperature is 250ºF
  • twenty-four hour cure time
Physical Properties:
  • Pour time: 30 mins
  • Demold time: 16 hr
  • Total cure time: 7 days
  • Specific gravity: 1.01
  • Mixed viscosity: 2,000 cps
  • Shore A Hardness: A30
  • Tensile strength: 281 (1.94) psi
  • Elongation %: 506
  • Linear Shrinkage %: Nil
  • Die C Tear Strength PLI(kzn/m): 62 (10.86)
Click here for TAP Urethane RTV Product Bulletin.
Click here for Choosing A Mold Material guide.

Click here for TAP Urethane RTV A label.
Click here for TAP Urethane RTV B label. 

TAP Video: How to make a simple urethane mold