How to Make a Plaster Mold

by Lisa Salisbury


  • #1pottery plaster
  • Water
  • 1x2 wood frame- mitered corners
  • Mold soap or silicone spray
  • Leatherhard clay tile
  • Soft clay for collet
  • Brush
  • Instructions

    Step 1

    Frame on soaped melamine surface, seal outside edge with clay

    Step 2

    Sealing edge

    Step 3

    Center tile in frame

    Step 4

    Brush soap or silicone spray over tile surface

    Step 5

    Weigh plaster 1937 g

    Step 6

    Add slowly to 1 quart of water, let sit for 2-3 minutes then stir slowly by hand breaking up clumps, not too fast you don't want air bubbles.

    Step 7

    When plaster thickens to heavy cream feel slowly pour into frame

    Step 8

    Fill frame

    Step 9

    Tap table with rubber mallet to bring any air bubbles to surface

    Step 10

    After plaster loses its sheen and has hardened some, invert and trim off any extra globs

    Step 11

    Use knife or metal strip to bevel all edges

    Step 12

    When tile starts to dry a bit, pry out and clean up mold edges

    Step 13

    Finished mold, let dry completely before use