SIlastic 3481 is our best quality silicone. Its toughness and flexibility together with the choice of curing agent speeds add up to make this Dow Corning silicone a leader in its field. Highly recommended when casting with resins, plaster, Jesmonite and concrete.
You can use the pigmented 10% Silicone Catalyst or the clear 5% Silastic 81 Curing Agent range.
The Silastic 81 Curing Agent gives a Shore A hardness of 24, and maximises tear strength, whereas the 10% Silicone Catalyst gives a softer 20 Shore A and a slightly weaker mould.
10% Silicone Catalyst: 1kg Base requires 100g, 5kg base 500g and 20kg base 2kg.
5% Silastic Curing Agent: 1kg Base requires 50g, 5kg base 250g and 20kg base 1kg.
Silastic 81-F (Fast) - this is the most common.
Gel Time: 30 minute
De-Mold Time: 5 hours
Silastic 81-R (Resin-resistant) - this is more resistant to polyester resin, so increases the mould–life.
Gel Time: 90 minute
De-Mold Time: 24 hours
Silastic 81-VF (Very Fast) - this really is Very Fast! So only use for specific applications.
Gel Time: 10 minute
De-Mold Time: 1½ hours
As a guide, the yield (or coverage) of 1kg Silicone is 1290 cm2 at 6mm deep.