How To Use Two Part Moulding Compound

Moulding compound is a room temperature vulcanising silicone which produces tough, strong, long lasting moulds ideal for using with precious metal clay (PMC). It is safe, non-hazardous and non-toxic and gives off no unpleasant fumes or odours. 

On this page we give instructions, tips and advice when using the compound to create moulds for metal clay jewellery designs, with examples from a project we created ourselves. 

Notes before you start

Take care not to start the hardening process by cross contamination

Great care must be taken not to accidentally contaminate and accidentally start the hardening process of the moulding compound within the bag – follow our instructions to ensure success. With a little care & common sense you will find this easy to avoid.

Always handle the green putty first as the white is the activating putty (this will cut down on the likelihood of unwanted contamination of the green putty).

Make sure you thoroughly wash and dry your hands in between handling the two colours. Never touch one colour and then the other, even when you are taking some out of the bag, as even this can start the hardening process.

Timing

Choose the item you wish to make a mould from and make sure you have it to hand – timing is crucial so you do not want to waste any of the 2 minute working time.

WORKING TIME = 2 MINUTES

CURING TIME = 15 MINUTES

The compound will leave an oily residue on your hands whilst working but do not worry – this is ordinary mineral oil, also commonly known as ‘baby oil ’.

How To Use...

Step 1

Take equal parts of both green and white putty (try to be as accurate as you can but these need not be measured precisely).

Step 2

Mix the two parts thoroughly. Try to mix quickly and remember a uniform colour is not necessary.

One simple method of doing this to ensure an even mix is described below:

  • Shape the two parts into thin ‘pancakes’ on a tabletop or work surface.
  • Place one ‘pancake’ on top of the other and then mix them rapidly by pushing down with your thumbs, kneading with both hands or rolling between the palms (we found that a combination of these techniques works best).
  • Do this for around 1 to 1 and a half minutes - be careful not to over mix! Over mixing can result in non-curing of the mould, the total moulding process must be complete within the 2 minute working time.

Step 3

When you have finished mixing firmly press the item you would live to create a mould from into the compound.

Step 4

Leave the mould for at least 15 minutes. Check it has cured by pushing a fingernail or similar into the mould – if the compound has cured properly it should spring back into shape.

Step 5

Carefully remove your object. Your mould is now ready to use and fill with metal clay.

If you have any further questions, feel free to call our friendly team who will be more than happy to give you some advice through Facebook, Twitter, Email or simply calling us on 01872 573888 8.30am-4.30pm.

Alternatively, for more information and how to's on all areas of jewellery making visit our other Gemstone Setting Advice pages.