Making a Hard Plaster Mould

Here I am making a very simple mould for making corner ornament. A silicon impression from an original carved boxwood mould will be used to make a new mould. The stages are:

• Make a fence from scrap wood
• Fix a piece of glass to the fence with double sided tape
• Smear the glass with petroleum jelly
• Weigh out 560g of hard casting powder and measure 200ml of water
• Stick the silicone impression to the glass
• Add the plaster powder to the water and mix well
• Pour the plaster into the fence

This will make a practical mould that can be used with compo or epoxy putty, not as crisp or refined as an original boxwood mould but a good alternative.