RTV High Temperature Resistant Mould Making Rubber 1kg Kit

RTV High Temperature Resistant Mould Making Rubber 1kg Kit


500g PART A + 500g PART B

Total Volume 876ml

Heat Resistant to 330°C

This material is odourless and non-toxic. Primarily used for the casting of low melt alloys for casting military figures, jewellery, model parts and dolls house accessories in lead/tin alloys or pewter. It can also be used for casting resins, waxes, plaster etc.


To view our range of Pewter casting alloys please



The two components mix easily by hand with a simple 1:1 ratio and because of the low viscosity can be used without a vacuum chamber. There is practically no shrinkage (0.08%) and excellent reproduction of fine detail. The cured material has a long mould life with outstanding release properties; there is no risk of the casting material sticking to the mould. As an addition/platinum cure rubber it has excellent dimensional stability and will resist deforming providing a long library life.

PART A is a grey liquid and PART B is a yellow liquid that react to form a strong, tough, flexible and elastic yellow rubber with excellent chemical resistance and is heat resistant to 330°C.

The colour of the cured rubber can be changed with the addition of a colour pigment during the mixing of the two components. We have a range of compatible colour pigments

Mixing Ratio: 1 : 1

Pot Life @ 25°c: 8-12 Minutes

De-mould Time @ 25°c: 1-2 Hours

Physical Properties Value
Viscosity mPas 25,000
Tensile Strength Mpa 4.4
Elongation 200%
Tear Strength kN/m 8
Shrinkage 0.08%
Shore Hardness A 45

 Inhibition Of Cure

Great care must be taken when handling and mixing all addition-cured silicone elastomer systems. All the mixing tools (vessels and spatulas) should be clean and constructed in materials which do not interfere with the curing mechanism. The cure of the rubber can be inhibited by the presence of compounds of nitrogen, sulphur, phosphorus and arsenic; organotin catalysts and PVC stabilisers; epoxy resin catalysts and even contact with materials containing these substances e.g. moulding clays, sulphur vulcanised rubbers, condensation cure silicone rubbers, onion and garlic.


All prices include VAT unless otherwise stated.

DWR Plastics - Silicone Moulding Kits, Rubbers & Resins