1. Mixing the two components

The components A and B are mixed by weight in the above indicated ratio. The mixing can be carried out either by hand or using a low-speed electric or pneumatic mixer to minimize the introduction of air and to avoid any temperature increase.

It is also possible to use a special mixing and dispensing machine for the two silicone components. Further information is available upon request.

2. Degassing

The mixture should be degassed preferably at 30 to 50 mbar to eliminate any entrapped air. If a dispensing machine is used, the two components are degassed separately prior to mixing. The silicone mixture expands to 3 to 4 times of its initial volume and bubbles rise to the surface. The bubbles progressively disappear and the mixture returns to its initial volume after 5 to 10 minutes. Wait a few minutes to complete the degassing and then flash the vacuum. The silicone is ready for pouring, either by gravity or under low pressure.

Note: Flashing the vacuum once or twice accelerates the degassing. It is recommended to use a container with a high diameter / height ratio.

3. Polymerization

The system polymerizes at 23°C. The curing may be slowed down by lowering the temperature and accelerated by adding heat.

4. Inhibition

Contact with certain materials can inhibit the crosslinking. See list below:

  • natural rubbers vulcanized with sulphur,

  • RTV 2 silicone elastomers catalyzed with metal salts, e.g. tin-compounds,

  • PVC stabilized with tin salts and additives,

  • epoxy resins catalyzed with amines,

  • certain organic solvents, e.g. ketones, alcohols, ether etc.

In case of doubts, it is recommended to test the substrate by applying a small quantity of the mixed silicone on a restricted area.

BLUESIL RTV 3621 QC B may be stored for up to 6 months from its date of manufacturing.Please consult the Safety Data Sheet of this product.


BLUESIL RTV 3621 QC A/B is a two component silicone elastomer that cures at room temperature by polyaddition reaction, at a 1:1 ratio. It is designed to be used for molding in a variety of applications that require a faster cure, particularly those requiring realistic skin feel.


2 Part RTV

  • Easy to use viscosity
  • Translucent – can be pigmented
  • Quick Cure
  • Excellent reproduction of details
  • Excellent mechanical properties
  • Low linear shrinkage
  • High resistance to inorganic chemicals and ultraviolet rays
  • Molding life like parts
  • Animatronics; special effect skins
  • Props for the film industry                                       
  • Theme park props and reproduction molds

North America




Viscosity7000PairedCompISO 2555cP




Viscosity7000PairedCompISO 2555cP






hardness_cd523e03-72a3-4261-93f9-36f7bbeeafb1hardness_cd523e03-72a3-4261-93f9-36f7bbeeafb1Hardness20PairedMixASTM D 2240sh.A
pot-life_0d649a54-7503-4c7c-a047-9d0c4b3e9f6apot-life_0d649a54-7503-4c7c-a047-9d0c4b3e9f6aPot life2.75PairedMixASTM C 603min
elongation_68a5ddf2-2baf-4e60-ac6f-0a8a18a758b2elongation_68a5ddf2-2baf-4e60-ac6f-0a8a18a758b2Elongation> 500PairedMixASTM D 412%
tear-strength_a14604f3-602f-4240-a9bf-15d90bbfbd13tear-strength_a14604f3-602f-4240-a9bf-15d90bbfbd13Tear strength> 56PairedMixlb/in
tensile-strength_e61eb2e0-4dc3-47b0-a61f-b673f1b265dctensile-strength_e61eb2e0-4dc3-47b0-a61f-b673f1b265dcTensile strength> 655PairedMixASTM D 412psi





BLUESIL RTV 3621 QC ABLUESIL RTV 3621 QC A/our_offer/Product/90060165/90060164/BLUESIL-RTV-3621-QC-A