HD Silicone mould-making compound

Our HD silicone mould-making compound is used for making long-lasting moulds with very high durability. HD stands for heavy duty. This silicone is ideal for the production of moulds for concrete casting, as it has an enormous tensile strength and at the same time enables easy demoulding due to its low Shore hardness. During processing, it is pleasantly low viscosity, so that it deaerates well even without vacuum technology. The pot life of approx. 12 minutes allows for quick and yet stress-free working.

The product is an addition-curing casting silicone consisting of two components that are mixed in a 1:1 ratio. Both components are transparent and remain so after mixing. This means that, unlike with other silicones, it is not possible to visually check the mixing result via the colour shade, which is why the mixing process should be carried out with particular care. The advantage of transparent silicone on the other hand is a particularly high tensile strength, as it does not contain any dyes that could affect the strength. In addition, it is often helpful to be able to see into the mould during the casting process.

By adding a silicone thickener, you can modify the mass so that it becomes trowelable and does not run down vertical walls. You can also find thickeners here in the shop.

The double container contains either 1 kg or 10 kg. The quantity of 1 kg is sufficient for a volume of 0.94 litres.

Technical data:
Colour: transparent (component A) and transparent (component B)
Mixing ratio: 1:1 by weight
Specific weight: 1.06 g/cm³
Viscosity: 3500 mPas
Mixing time at 20°C: 1 minute
Working time (pot life) at 20°C: 12 minutes (100 g)
Curing time (demoulding time) at 20°C: 140 minutes
Shore A hardness after 24 hours: 20
Breaking load (tensile strength): 6 N/mm²
Elongation at break: 480
Dimensional change after 24 hours: < 0.1 %
Shelf life: at least one year

Attention: When working with addition-curing silicone rubbers, make sure that clean and dry containers are used. The surface of the object to be moulded should also be as dry and free of impurities as possible. Certain substances can prevent or slow down the curing of addition-curing silicone. These include condensation-curing silicones, organic rubbers, plasticizers, amines, heavy metals and sulphur-containing kneading compounds. At the contact surfaces between addition-curing silicone and the substances mentioned, vulcanization problems then occur, which render the mould and often also the model unusable. In case of doubt it is strongly recommended to check the material compatibility in a small preliminary test.

Moertelshop provides you with practical tools and materials for art, design, building and tinkering with concrete at a fair price. Order from us online and take advantage of our unbeatable cheap shipping.