Updating and Repairing Silver Clay Pieces.
Sometimes I like to revisit an earlier piece or update it for a new look...with unfired clay this is easy (use slip) but when pieces have been fired you need to either:
1) Make a mechanical bond, like drilling a hole and attaching the new piece by squeezing it on (this then forms it's own little rivet when fired).
2) Or attaching the fired pieces with a special type of paste.
There is something called Art Clay Oil Paste which makes a very strong bond for connecting 2 previously fired pieces
It costs about £15 though so I'm going to show you how to make your own version!
Making Lavender Oil Paste
Lavender oil can be added to silver clay paste to make your own oil paste. Gradually add pure lavender oil drops to a thick PMC or ACS paste mixture (15-30 drops). Stir with a plastic spatula or wooden stick until it binds together. Let it sit overnight to assure complete absorption before using. You can make Lavender Oil with PMC plus, PMC3 and all Art Clay products.
Attaching the fired pieces
When you want a strong bond on fired pieces Oil paste is a must!
Here's how I do it:
1) Roughen the surface of the parts where they're to meet (or
put them back in the kiln again for 10 mins) that gives them a rougher texture to adhere to.
2) Attach the 2 pieces with a good gob of paste & for extra "stick" add slip to seal in the edges
3) Let air dry slowly or overnight
4) Try not to wiggle the pieces too much as (until they're fired) the bond still isn't as strong as when you use slip on unfired pieces.
Fire at the hottest temp your clay and inclusions can stand preferably for at least 2 hrs.
(I use 850 degrees)
Extra Info:Here's a useful article by the PMC guild which shows some strength tests using lavender oil paste.
Art Magazine has a making lavender paste video (you have to join but I think it's free).