What Is #3475 Urethane Casting Resin? #3475 Urethane Casting Resin is a white, two-part casting urethane with 75 Shore D hardness, made for final parts and short-run castings where superior cosmetic qualities and stiffness matter. It has a simple 1:1 mix ratio, and its low mixed viscosity lets it fill complex molds and be hand injected into detailed cavities. Cured castings are bright white with good tensile strength and superior stiffness in thin sections. Why Choose #3475 Urethane Casting Resin? The combination of 75 Shore D stiffness, bright white color, and low viscosity makes #3475 a strong choice for detailed, high-performance parts. It is used for casting prototypes that simulate molded parts, for preproduction checking of injection molds, and for automotive, aircraft, and marine parts and tooling. The 1:1 ratio keeps mixing simple and repeatable. For tough industrial castings where toughness matters more than cosmetics, see the 60 Shore D #3460. For flexible parts and molds, the Shore A urethanes are the right choice. What Are the Best Applications for #3475 Urethane Casting Resin? #3475 Urethane Casting Resin is well suited to short-run production parts, detailed prototype castings, injection-mold preproduction checks, and automotive, aircraft, and marine parts and tooling where stiffness and cosmetic quality are priorities. How Should #3475 Urethane Casting Resin Be Used for Best Results? #3475 Urethane Casting Resin mixes 1:1 by volume. Mix thoroughly and pour slowly to help air bubbles release. Avoid water and all moisture contamination, and do not use PVA Release Film, wooden stir sticks, or paper containers. Use #2333 Plastic Paint Stirrers and release with at least four layers of #4121 Non-Silicone High Temp Paste Wax. Demold heavier sections in 4 to 6 hours at 77 degrees F. Most applications reach working strength in 18 to 24 hours and full cure in 7 days at room temperature. Cure can be accelerated by oven curing after gel: 150 degrees F for 2 to 3 hours or 120 degrees F for 4 to 6 hours. For final parts and short-run castings, this white Urethane Casting Resin with 75 Shore D hardness can create detailed parts with superior cosmetic qualities. #3475 Urethane Casting Resin has a simple 1:1 mix ratio, and its low mixed viscosity makes it an ideal material to fill complicated molds. Cured castings are bright white and have great physical properties including: good tensile strength and superior stiffness in thin sections. #3475 Urethane Casting Resin is a great material for high performance parts and castings. It can be used for the casting of prototypes to simulate molded parts or for the preproduction checking of injection molds. Common application include automobile, aircraft and marine parts and tooling. As a low viscosity material, it can be hand injected into the most detailed cavities. When mixed thoroughly, pour the urethane slowly to aid the release of air bubbles. When using Urethane Casting Resin – 75 Shore D kits, avoid water and all types of moisture contamination. Do not use any urethane kit with PVA Release Film, and do not mix with wooden mixing sticks or in paper mixing containers. #2333 Plastic Paint Stirrers for Urethanes are recommended. To ensure a proper release from a mold, use at least four layers of #4121 Non-Silicone High Temp Paste Wax. #3475 Urethane Casting Resin can fully cure at room temperature. Demold time for heavier section castings is 4 to 6 hours @ 77°F. Castings will develop strength sufficient for most applications in 18 to 24 hours at 77°F, and reach full cure in 7 days at room temperature. The full cure can be accelerated by oven curing after the material gels at room temperature. Oven cure at 150°F for 2-3 hours or oven cure at 120°F for 4-6 hours. Heat curing will increase the heat distortion temperature, and therefore improve the heat stability of the cured material. Mix Ratio (by weight) – 100:100 Color – White Working Time, 4 fl. Oz. mass @ 77°F – 30-40 minutes Technical Specifications Type: Two-part urethane casting resin, white, 75 Shore D Mix ratio: 1:1 by volume Demold (heavier sections): 4 to 6 hours at 77 degrees F; full cure 7 days at room temperature Oven cure option: 150 degrees F for 2 to 3 hours, or 120 degrees F for 4 to 6 hours, after room-temperature gel Do not use with PVA Release Film, wooden sticks, or paper containers; release with four layers of #4121 wax Available Sizes and SKUs #3475-A - Quart kit (Part A and Part B each in quart containers) #3475-B - Gallon kit (Part A and Part B each in gallon containers) Every product Fibre Glast sells is First Quality Guaranteed, so you can cast detailed parts with confidence.
