Mold Making

This is a page about making molds. It will be focused on rubber molds (polyurethane rubber, silicone).

Factors to consider when making a mold

• 1 part, 1 part tear, or 2 part mold
• Mold box
• Mold release
• Rubber hardness & viscosity
  • Shore hardness
  • Vacuum degassing
  • Pressure casting
• Master material
  • Porosity & sealing
  • Materials that inhibit curing
    • Sulfur
    • Some plastics (see below)

Making mold of 3D printed parts

Cure inhibition

• SLA resin

Mitigating cure inhibition

• https://joshuawoehlke.com/curing-silicone-in-sla-uv-molds-part-3/
• Inhibit X
• Using polyurethane rubber or tin cure silicone instead of platinum cure silicone
• Sealing with acrylic (e.g. Krylon Crystal Clear)

Resources

Where to get mold making materials

• Reynolds Advanced Materials (Denver)
• Sculpture Depot (Loveland)
• Rio Grande