1. Stir the base (Part A) well before use (except when machine dispensing).
  2. Shake the catalyst container (Part B) well before use.
  3. Weigh the desired amount of base into a clean mixing container. Tip the container and roll the base all the way  around the side wall up to two inches from the top. This will prevent the catalyst from becoming absorbed into the container. It is recommended that the container be filled to not more than 1/3 the container depth to allow sufficient room for expansion during the deaeration procedure.
  4. Weigh the proper amount of catalyst into the container. Mix the base and catalyst together by stirring with a stiff, flat ended metal spatula until a uniform color is obtained. Scrape the container walls and bottom well to insure a thorough mix.
  5. Place the container into a vacuum chamber and evacuate the entrapped air from the mixture using a vacuum pump capable of achieving 29 inches of mercury vacuum. The mixture will rise, crest and then collapse in the container. Interruption (bumping) of the vacuum may be necessary to prevent overflowing the container. Keep the mixture under full vacuum for 2-3 minutes after the material has receded in the container.
  6. Bleed air slowly into the vacuum chamber. When the chamber is at atmospheric equilibrium, remove the cover plate and take out the container.
  7. Pour the deaired material slowly in a steady stream from one end of the mold box so that the material flows evenly over the pattern.  This should minimize entrapment of air bubbles under the flowing material. A "print" coat may be poured first over the pattern which will also help reduce the possibility of entrapping air on the pattern and in the cured rubber. A mold release (petroleum jelly) may be applied on the pattern first to improve release.
  8. Allow the rubber to cure for 16-24 hours at 75±5°F (24°C) before removing the cured rubber mold from the pattern.
    Heat acceleration is not recommended with this product.
  9. For best results, allow the mold to air cure an additional 24 hours before using it in production.  Full cure is achieved in 3-7 days.
  10. For bonding to wood or metals, use BLUESIL V-04 primer.  Follow recommendations on the BLUESIL V-04  technical data sheet for best results.



  1. For best results, mix and cure the material at 75°F (24°C) and 50% relative humidity.
  2. Higher temperature and humidity will decrease the work life and pot life of the material. The faster cure will also affect the flow properties. Refrigeration of the base prior to use in hot environments has shown to improve the handling properties of this material.
  3. Lower temperatures and humidity will increase the work life and pot life of the material. The slower cure will increase the flow time. Cure temperatures below 68°F (20°C) are not recommended and have been found to cause a reduction in final cure hardness and properties.
  4. It is important that the catalyst containers are tightly closed after use. Catalyst exposed to air for extended periods of time will hydrolyze (cure). An indication of hydrolysis is a film or crust formation on the surface of the catalyst. The use of hydrolyzed catalyst is not recommended and may cause incomplete cure.
BLUESIL RTV 573 may be stored at a temperature below 40°C / 104°F for up to 18 months from its date of manufacturing.Please consult the Safety Data Sheet of this product.


BLUESIL RTV 573 is a low viscosity liquid silicone product which, after the addition of a curing agent, cures at room temperature to a strong, flexible silicone rubber for moldmaking and tooling. Molds made from BLUESIL RTV 573 have been used to produce reproductions from filled or extended polyesters, epoxy, polyurethane and plaster casts. The high elongation and low hardness of BLUESIL RTV 573 enables easy release of patterns with deep undercuts and intricate details. BLUESIL RTV 573 does not contain pigments that could stain valuable original models.


2 Part RTV

• Highly detailed reproductions of figurines, statuary and artifacts

• Compatible with polyester, epoxy, polyurethanes and other casting materials

North America