GI-1000 is an extremely high tear-strength, tin-catalyzed RTV-2 silicone rubber, which was designed for casting epoxy resin and polyester parts. GI-1000 is not sensitive to inhibition, meaning it will cure at room temperature over virtually any surface. It is easy to mix and de-air, and will cure with only a slight degree of shrinkage. The speed at which the rubber hardens can be accelerated with special activators. Condensation cure, two-component silicone rubbers are excellent for most general mold making and prototype applications. GI-1000 is extremely useful for those applications where superior mechanical properties are required.
Extremely high tear-strength: GI-1000 is especially good for molds with deep undercuts and for those molds which require flexing for part removal.
Low shrinkage: GI-1000 offers exceptional reproduction capability. It is particularly valuable in the production of many-sided molds where exact registrations are required.
Excellent chemical resistance: GI-1000 exhibits extremely long mold life due to unique processing techniques that were developed to meet the rigors of polyester and polyurethane casting.
Low viscosity: The low viscosity of GI-1000 allows for easy mixing and de-airing, ensuring smooth, even flow.
Color-coded catalyst: The blue GI-1000 activator ensures homogeneous mixing and eliminates mold loss resulting from inadequate stirring.
Long pot life: GI-1000 gives good overnight cure despite having a working time of two hours. In addition, it is relatively insensitive to temperature and humidity fluctuations.
Insensitive to inhibition: GI-1000 is not inhibited by most common mold-making substrates, eliminating the need to use mold sealers.
Good dielectric properties: GI-1000 provides excellent electrical insulating characteristics over a wide temperature range and is especially suitable for applications where mechanical stresses are involved.
Low cost: GI-1000 has a low specific gravity, which means less of it is required than RTVs with a higher specific gravity. When the long mold life is combined with the low specific gravity, GI-1000 is a cost-effective, high performance RTV silicone rubber.
Measure the RTV silicone Base into a disposable container that is approximately four times the volume of the rubber. Accurately add the exact amount of Activator required.
Thoroughly stir the mixture with a flat blade spatuala or with mechanical mixing. Be sure to scrape the sides and bottom of the container to ensure the correct ratio of Base to Activator. Stir slowly until a uniform color is achieved without streaks.
Place the mixed RTV silicone rubber into a deaeration chamber capable of 28 to 29 inches of mercury vacuum. Allow the rubber to expand and collapse back to its original volume. Maintain vacuum for an additional one to two minutes. Release vacuum and remove the container from the deaeration chamber.
The part to be duplicated should be coated with a mold release agent (MR-15 is recommended) to ensure easy separation. The part should be placed into a box that will contain the silicone rubber while it is a liquid. Slowly pour the mixed silicone rubber over the released pattern being careful to avoid the formation of air bubbles or entrapped air. Allow the rubber to flow around the part to a minimum depth of 3/8 to 1/2 inch.
Allow the rubber to vulcanize for 16 to 18 hours at room temperature (70oF). Lower temperatures and/or low humidity will cause the cure time to lengthen; conversely, higher temperatures and/or high humidity will cause the cure time to shorten.
Partially disassemble the mold box and remove the cured block of RTV silicone rubber. Carefully flex the mold to remove the original part.
The silicone mold is ready to be used with appropriate casting materials to duplicate the original pattern.