Lightweight Fast-Setting Tooling System


REPLICAST Light is a lightweight fast-setting urethane casting system with good handling and cured properties. It was developed to provide a fast, economical casting system for a variety of applications. It has good compressive strength, so it works well as a lightweight, strong back-up material. It is readily machinable, so changes can be easily made. Lightweight holding and nesting fixtures are another logical use for this versatile material.


Two-component systems with lightweight fillers added will separate in storage after a very short time, with the lightweight fillers actually floating to the top of the storage container. Remixing these components is tedious and time consuming, and often results in an inconsistent mixture. 
To avoid these problems, REPLICAST Light is provided as a three-component system, where the lightweight filler is added at the time of use. For the best results and highest physical properties, mix the three components by weight. For less critical applications, the components can be measured by volume- but still try to be as accurate as possible. In either case, the Part C lightweight filler is added to the Part B and then “let down” with the Part A.
In three separate containers, measure out the required amount of all three components needed for the casting to be made. Make sure the Part B is in a container that will hold all of the components to be used. Start the mixing process by adding half of the Part C lightweight filler to the Part B container and mix until smooth, then add the remaining Part C and continue mixing. At this point, you will have a creamy, yet thick, somewhat pasty consistency material. Then slowly add the Part A component and mix it into the Part B and Part C combination. Very quickly, you will achieve a smooth, liquid viscosity material that will be very easy to pour. When the mixture is uniform, cast the material and allow to cure.
REPLICAST Light will gel quickly, and castings can be demolded rapidly. The demold time will depend upon casting size and thickness, and shop temperatures. At a 77°F ambient shop temperature, castings of 3″ or more thickness can be demolded in around 30 minutes. Thinner castings may take longer, up to an hour. At this point, the casting can be used in non-critical applications. However, if maximum physical properties are required, the material should be allowed to cure longer.

ASTM Method
Mix Ratio, by Weight
88 Part A : 100 Part B : 100 Part C
ColorLight Gray to Grayish Brown
Mixed Viscosity, @ 77°F
3750 cps
Working Time, 4 fl. oz. Mass @ 77°F
6 – 8 minutes
Cured Hardness, Shore D
73 Shore D
Shrinkage, in./in., Mold # 1, Vol: .053 Gal
Specific Gravity, grams, cc
Density, lb./cu. inch
Specific Volume, cu. in./lb.
Tensile Strength, psi
2540 psi
Elongation @ Break, % 3.6 %
Tensile Modulus, psi493,887 psiD638
Flexural Strength, psi
5430 psi
Flexural Modulus, psi474,360D790
Compressive Strength, psi
5608 psi
Compressive Modulus, psi252,505 psiD695
Izod Impact Strength, Method A, Notched.21D256
Glass Transition Temp., Tg, DMA   E’, Onset, Peak138°F, 196°FD4065

Gallon Kit
Pail Kit
Part A
8 lb.
40 lb.
Part B
9 lb.
45 lb.
Part C2 Gallons @ 4.5 lb. ea.
2 Pails @ 22.5 lb. ea.
Kit26 lb.130 lb.