How To Make a 1‑Piece Silicone Cut Mold


Mold Star® 15 is perfect for experienced mold makers or people just starting out. It is an easy to use silicone rubber that offers performance other mold making rubbers do not:

  1. Easy To Use – the mix ratio is 1A:1B by volume… no weighing scale necessary.
  2. No Vacuum Degassing Necessary – Unlike other platinum silicones, Mold Star® de-airs itself resulting in bubble-free molds.
  3. Long Working Time – Pot life is 50 minutes at room temperature, offering time to make molds of large models.
  4. High tear strength and other great performance properties.
  5. Minimal long term shrinkage.
  6. Very long library life of many years.

Fully cured rubber can be used to cast low-temperature melt metal alloys, urethane, epoxy or polyester resins, wax, plasters or concrete.

Important: Mold Star® 15 cannot be used with modeling clays containing sulfur. Even if the model is sealed.

Materials Used in this Tutorial

  • Mold Star 15
  • Smooth-Cast ONYX
  • SuperSeal
  • Hot Glue
  • Ease Release 200
  • Mold Strap
  • Paint Brush
  • Mixing Containers
  • Mixing Sticks