Thursday, February 7, 2008

Comissioned 18kt Gold Butterfly Moulding

So I made this gold flutterby. It is a pendant. The chain will go through the feelers. In the top wing red jasper will be set and the bottom one will be zugalite, a purple stone .
I have to cut them still, and they will be about 1-1.5 mm thick.
But I first mould the thing.
The sprue is made out of silver. Notice how the center one does not aline. That is no problem, because I will cut it correctly once the silicone has cured. The reason it is un-alined is because I only soldered one of the side sprues. No point in soldering all of them. It just means that more has to be cleaned up after they have been removed.
I use a clear-ish silicone moulding product from A good company, good product and it cures quickly too. They sent me a free product sample and now that it is finished, I am ordering more.
I am moving away from hot moulds on jobs like this. There is more accurate representation with cold cure moulding and I like the fact that there is little shrinkage, especially with pieces that have prongs, such as this one.
I 'glue' the red part of the box to the clear part with hot injection wax. This allows me a good seal and also allows me to remove the red piece easily when the mould has to be removed out the box.

I have mixed the two components and vacuumed them . Then I pour the silicone into the box and vacuum again.
Then I over fill the box and put another piece of Perspex on top with a weight on top. It slides off easily at first , as shown, but afterwards all the silicone is squashed out and then I let the mould cure. The plastic is easy to remove once it is cured .
Tomorrow or the next day I will show the finished piece and the injected wax.