Polycraft OptiCast 3000 Water Clear Polyurethane Casting Resin

Mould Preparation

Before use ensure that the master model from which the mould is made has the exact finish that is required in the cast or finished units, i.e.. for optimum clarity polish the master model to a very high sheen. Ensure that the mould is clean and dry. If the mould is made from metal or resin, use a release agent. Condensation cured silicone rubber should not be used with OptiCast 3000. It may be necessary to preheat the mould to 40°C in order to prevent shrinkage at the corners and sides of the casting.

Resin Preparation
Open both A and B containers and examine for any signs of crystallization, place in the oven at 45 – 60°C if any crystals are observed. Ensure that both components are between 20 – 25°C before mixing. If using pigments, add the pigment to the part A.

Mixing instructions

Do not use paper cups or wooden mixing sticks as these may introduce moisture to the mix which may cause excess air in the cast or cure inhibition. Mix the two components at the correct ratio, mixing carefully to avoid air inclusion and making sure the material at the sides and bottom of the mix vessel is well stirred into the middle. The material may become cloudy in appearance for a few minutes. Pour the material into the mould, ideally onto the sides and in one place to reduce air bubbles

Curing
If the casting has thin sections, it is advisable either to use preheated moulds (see “Mould Preparation” above), or to post cure the castings after gelation in an oven at 40 – 50°C for 3 hours. Allow the casting to cure for at least 48 hours before machining or polishing. To avoid distortion ensure that the material does not reach temperatures above 60°C during machining or polishing.