Moulding & Casting

Making the mould

• Using a hot glue gun, glue a dowel (little piece of wood) onto the end of a walnut and glue it to the centre of a small piece of plastic. 

• Cut a strip of plastic into 4, big enough to make walls around the walnut. 

• Place plastic walls one by one around the walnut. Use plastic solvent on the base of the walls to set them in place. (Paint base edges with paintbrush dipped in solvent.)

• Use hot glue gun to fill gaps showing between the plastic walls. 

• Mix silicone liquid with hardener. (Using 10-1 ratio) = mix 170g of silicone liquid and 17g of hardener. (1/3 - 1/2 cup full.) Wear goggles, mask and gloves for this!!

• Place this pot into the vacuum degassing machine. Place the lid on top and turn the handle on the left hand side. Wait till the dial goes to the 7 o'clock position and open handle slowly. 

• Pour mixture onto the side of one wall and let it run into the box with the walnut in. 

• Burst the bubbles at the top and leave to set for a few hours. 

• Break away the plastic walls and cut the mould so that you can remove the walnut inside. Cut 2 small holes inside the mould at the top, leading from the walnut impression to the very top of the block. This is where the resin will be poured to cast a walnut and the other hole will release air as the mould is filling up. 

Casting

• Mix the resin on a one to one ratio. Mix 60g of part A of Fast Cast (a polyurethane resin) and 60g of part B. Wear goggles, gloves and mask for this!

• Put masking tape around moulded block and pour mixture in through one of the holes. Leave for 20 minutes. Once set you'll have a moulded walnut! you can use the mould many more times to make duplicates.  

Making flat objects e.g a medal 

• Make your object from clay on a wooden board and leave to set. 

• Mix silicone liquid and hardener (like the walnut mould) and pour over. (Make plastic walls like walnut demo again before pouring on silicone!) Wear goggles, gloves and mask for this!

• Wait till it sets and remove mould. This would have picked up all the detail you made on the clay version. 

• Mix Fast cast resin (part A and B) and pour into mould. Spread mixture evenly with a stick, put something heavy on the top of the mould and leave it to set. Wear goggles, gloves and mask for this!