Tin Silicone Mold Rubbers

tin-silicone-mold-rubbersTinSil® tin-cured silicone liquid mold rubbers are two-part (Part A & Part B), room temperature curing systems; they are available in a variety of hardnesses. Molds made from these rubbers exhibit high tear strength, good release properties, and resistance to high temperatures.


  • Do not require release agents when casting.
  • Excellent chemical resistance.
  • These rubbers can be poured as supplied or thickened with TinThix liquid thickener for brush-on molds. A brushable/sprayable version called TinSil Brush/Spray 25 is available for use by hand or with low cost, portable equipment.


Typical Uses & Casting Materials

  • Resin casting (polyurethane, polyester, epoxy)
  • Foam casting
  • Wax casting
  • Sculpture reproduction
  • Soap and candle making
  • Plaster casting
  • Cold cast bronze art
  • Low-melt metals


NOTE: TinSil molds do have a limited shelf-life when cured (library life) so they are not recommended for extended storage. TinSil 80-Series molds are designed for longer library life compared to TinSil 70-Series and other available tin silicone systems. TinSil liquid rubbers also shrink slightly on cure (~1%). For silicone rubber options with longer library life and no shrink on cure, view our platinum silicone rubbers.

There are two series within the tin silicone mold rubber line:

Tin Silicone Rubbers

TinSil® 70-Series 6 individual product options. Shore A10 to A60 hardness range. Includes two translucent rubber options. 1A:10B, 2A:100B, and 5A:100B mixes available. Demold times ranging from 16 hours to 24 hours. TinSil Brush/Spray 25 (a self-thickening rubber) and TinSil 70-60 (suitable for casting low-melt metals) are included in this series.
TinSil® 80-Series 3 individual product options. Shore A15, A30 & A40 hardness options. Only 1A:10B mixes available. 24 hour demold times. 80-Series rubbers have a longer library life than 70-Series rubbers.


Video Tutorials

This video features the making of a poured TinSil 70-25  (in the TinSil 70-Series) blanket mold:


This video features the making of a TinSil Brush/Spray 25 (in the TinSil 70-Series) brush-on mold of a rock:


For additional video tutorials, visit the Polytek YouTube Channel you-tube