1. Stir the base (Part A) well before use (except when machine dispensing).
2. Shake the curing agent 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 curing agent from being absorbed into
the container. Do not fill the container more than 1/3 full to allow sufficient room for expansion during the
deaeration procedure.
4. Weigh the proper amount of curing agent into the container.
5. Mix the base and curing agent together by stirring with a stiff, flat ended metal spatula until a uniform color is
obtained. Scrape the container walls and bottom to assure a thorough mix. If mechanical mixer is used, do not
exceed 150 rpm.
6. 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 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 a full vacuum for 5-10 minutes after the material has receded in the container.
7. Bleed air slowly into the vacuum chamber. When the chamber is at atmospheric equilibrium, remove the cover
plate and take out the container.
8. 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 will minimize the entrapment of air bubbles under the flowing rubber. A "print"
coat may be poured first over the pattern, which will also reduce the possibility of entrapping air in the cured
rubber. A mold release (petroleum jelly) may be applied on the pattern first to improve release if desired.
A. ROOM TEMPERATURE CURING SYSTEMS: Allow the rubber to cure for 16-24 hours at 75°F (24°C) before removing the cured rubber from the pattern. For best results, allow the mold to air cure an additional 24 hours after the initial overnight cure before putting mold into production. Room temperature curing assures the lowest possible shrinkage. If cure acceleration is desired, mild heat may be employed. To minimize shrinkage, cure rubber at 100-130°F (38-54°C) for 4-6 hours. Higher temperatures may cause excessive shrinkage to occur.
B. HEAT CURING SYSTEMS: BLUESTAR SILICONES heat-curing systems are primarily used for roll and transfer print pad applications where long work life and pot life are needed. FOLLOW THE SUGGESTED PRODUCT CURE SCHEDULE GUIDE LISTED ON FRONT OF SPECIFIC PRODUCT INFORMATION SHEET.
10. For bonding to wood or metals, use BLUESIL V-04 primer. Follow recommendations on the
BLUESIL V-04 primer technical data sheet for best results.

A decrease in work life and pot life may be expected to occur at temperatures exceeding 75°F (24°C). Room
temperature curing moldmaking rubbers are particularly sensitive to higher temperatures. Refrigeration of the base
(Part A) prior to use in hot environments has shown to improve the handling properties of these materials.

Lower temperatures will increase the work life and pot life of this material. Cure temperatures below 68°F (20°C) are
not recommended, and have been found to cause a reduction in final cure hardness and physical properties.

This system contains a platinum catalyst, which may be inhibited by materials found in some organic polymer systems,
chlorinated solvents, and some substrates. Especially troublesome materials are: amine cured epoxies, sulfur cured
organic rubber systems such as natural rubber, polysulfide rubber, latex rubber and adhesives, sulfur containing
modeling clays, PVC coated surfaces, and tin catalyzed silicone RTV rubbers. A patch test to determine compatibility is
recommended when doubt exists.

BLUESIL V-340 may be stored for up to 24 months from its date of manufacturing.Please consult the Safety Data Sheet of this product.


Bluesil V-340 is a two component, addition reaction, room temperature or heat accelerated cure silicone rubber compound. It is designed as a variable hardness rubber with high strength properties, long library life, excellent detail reproduction, excellent release characteristics, and improved resistance to inhibition. The specific hardness is dependent on which curing agent is used. Bluesil V-340 is an excellent choice for pattern shop, model shop, and Stereolithography service bureau mold making and tooling applications.


2 Part RTV

• Conventional production and prototype molds

• Finished rubber parts

• Stereolithography (SLA) molds

• Casting Architectural moldings

North America