How To Make a Silicone Mold Using Mold Star™ 15

Overview

This instructional mold making tutorial video shows how to make a silicone block mold for casting resin, wax, foam, and many other materials using Smooth-On Mold Star™ 15 platinum silicone mold rubber.

  1. Use hot glue to secure the model.
  2. Glue the mold box to the base.
  3. Dispense equal amounts Parts A & B into mixing container.
  4. Mix Parts A & B as directed.
  5. Slowly pour into one corner of the mold box. Pour 1/2 inch (1.25cm) over model's high point.
  6. Allow Mold Star 15 to cure.
  7. Carefully remove the mold box.
  8. Slowly peel back the cured rubber. Mold Star™ 15 reflects perfect detail.

Mold Star™ 15 is an easy to use Shore 15A platinum silicone that is mixed 1A:1B by volume (no weighing scale necessary). It features a relatively low viscosity and vacuum degassing is not required for most applications. Pot life is an extra-long 65 minutes. Mold Star® 15 cures overnight to a soft, strong rubber that is tear resistant and exhibits very low long term shrinkage.

Step 1: Secure the Model

Use hot glue to secure the model to the baseboard.

Step 2: Construct a Mold Wall

Glue the mold box to the base.

Step 3: Dispense

Dispense equal amounts 1A:1B by volume.

Step 4: Combine

Dispense parts A and B into mixing container.

Step 5: Mix

Mix parts A and B as directed, carefully scraping the sides and bottom of the mixing container.

Step 6: Pour

Slowly pour into one corner of the mold box.

Step 7: Mold Wall Thickness

Pour 1/2" (1.25 cm) over the model's high point

Step 8: Cure

Allow Mold Star™ 15 to cure, it has a cure time of 4 hours at room temperature (73°F/23°C)

Step 9: Remove Mold Box

Carefully remove the mold box from the baseboard.

Step 10: Demold

Slowly peel back the cured rubber.

Step 11: Finished

Mold Star™ 15 reflects perfect detail.

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