Polyurathane is available in a wide range of categories, these are:
- Rigid Polyurathane. So called Fastcast Polyurathanes, these set in a few minutes and take on the every detail of mould. Used for decorative, automotive and industrial applications. It can be pigmented. It is however hard on silicone moulds. Allow for mould change every 25 castings to maintain detail.
- Flexible Polyurathane. This is a dense Polyurathane that is great for casting concrete. It is available in range of Shore Hardnesses, from medium to hard, but not solid.
- Rigid Expanded Polyurathane. This is the material commonly used in refrigeration insulation and decorative mouldings. It takes the detail of the mould in the form of a ridged skin. It can be coloured by spraying a pigmented coat into the mould and then backing it up with the expanded Polyurathane. It is also available in Aerosol cans to use as a quick filler and insulator, great to create instant rocks and sculpture material.
- Flexible Expanded Polyurathane. This is the material that makes what we know as foam rubber. It can be cast into metal moulds using a silicone mould release. It forms a slight skin over the expanded material, an example os the little squeezy balls that kids and pets play with, is this material.
- Skinned Expanded Polyurathane. This is the material that car steering wheels and faux leather panels in cars and office furniture are made from. Highly technical to use, but when you get it right, it is amazing. Colour is sprayed into the mould and then backed up with the skinned flexible polyurathane