PC15 Water Clear Polyurethane Casting Resin

This rather depends on the environment the sculpture would be in because you will need to consider the UV stability of the resin you use. Also, it's not clear from your question whether you need the resin to be thick (like a filler) so that it can fill gaps or whether a normal liquid viscosity would be OK.

I'll assume that this is either an indoor or a semi-shaded environment (not permanent direct sunlight) in which case our XCR Coating Resin is a clear epoxy resin that would be liquid in its normal state, allowing you to direct it into cracks or gaps in the piece. It also has excellent UV stability (for an epoxy resin) so providing you're not looking at permanent direct sunlight then it should be fine.

If you need a thicker consistency then you'll find that anything you add to make the resin thicker will affect its clarity (making it milky) which may or may not be a problem. If you do want to make the resin thick (like a filler) then you could add Fumed Silica which is a white powder that can be added to resins to make them thick and self supporting.

Glass Bubbles can be added to most resins to reduce the density of the cured material. However, bear in mind that they will reduce the clarity of the GlassCast resin, making it more of a translucent 'milky' appearance rather than transparent.

Yes you can. For best results we recommend pouring any subsequent layers once the previous layer has become firm and tacky but not fully cured. This way you should be able to achieve a nice uniform optical clarity throughout the casting (i.e. no whiteness-mark from the join line. Given the fact that the resin is quite reactive, this method of multiple pours is necessary for larger or thicker castings.

No we would not recommend its use in this application for actual vehicle headlights. The resin would not have the mechanical durability and the heat resistance for use as an actual headlight lens. However, for scale model applications, these issues are not a factor and as such the resin could be used to replicated a model car headlight lens.

The toxic to aquatic life statement on the datasheets refers to the uncured components (in their liquid form). Once cured the resin should be totally stable and inert. However, it is possible to for a product to be officially tested and certified as 100% safe for aquatic life which this product has not undergone.

Like most water clear resins, you'll tend to get best results from addition cure (platinum cure) silicone moulds however we have found that we do get good results when casting this resin into our CS25 condensation cure silicone. You're most likely to run into problems if the resin exotherms excessively during cure (so, for larger castings where the resin will get hotter) because this can heat the silicone mould and drive moisture out of the silicone which reacts with the resin (i.e. causes small air bubbles). For smaller castings where the resin doesn't heat up excessively, we haven't seen any issues.

As for the viscosity, it's really very low and will flow and fill a mould quickly and easily.

Does this casting resin have the same tackiness properties as the polyester casting resin when cured exposed to the air?

Our Water Clear Polyurethane Casting Resin does NOT cure with a tacky finish when exposed to air, such as the top of an open mould. It cures to a hard and tack free finish.

The Water Clear PU casting resin is a very low odour resin. However, it is a professional product and it's still very important to work in well-ventilated area and follow all the precautions outlined in the Safety Data Sheet. Once correctly cured, the plastic will be totally inert and odourless.

Our Water Clear PU resin can be cast in sections as thin as 2mm. This should be fine for the larger scale models where a thicker section works fine. However this may mean that small scale models the resin is unsuitable.

No, our Water Clear PU has a fairly low heat distortion temperature of 48-50°C and as such would likely be marked and damaged by hot drinks and plates.

Yes, it's Shore D (i.e. it's very hard). I've now added this information to the product page to help others.