WHICH SILVER PASTE SHOULD I USE?
There are three primary formulations of silver metal clay paste: regular, overlay, and oil paste.
Regular paste, also called “slip,” is essentially a watered-down version of metal clay. Art Clay makes one version, using their 650 formula; PMC makes two versions, using both PMC+ and PMC3 formulations. Usage: Primarily with unfired metal clay to join elements, fix small flaws, and create embellishments
Art Clay Silver Overlay Paste has a different binder than regular paste and was formulated to create a strong bond with nonporous surfaces. Usage: To embellish glass, porcelain and other glazed ceramics; to join new unfired clay elements to already fired silver clay pieces
Art Clay Silver Oil Paste is the only paste that is not water soluble; it comes with its own thinning liquid. It is never used with unfired clay. Usage: To join metal clay elements that have already been fired; to make post-firing repairs
Which one works with gold paste?
In my experiments, I found that both Art Clay and PMC versions of gold paste were likely to flake off if applied directly to fired silver. A priming coat of regular silver paste (of any brand) improved results somewhat. But only with the use of Art Clay Silver Overlay paste did I achieve consistent results where the gold paste didn’t chip or peel off of the finished piece.
Why is my gold peeling or flaking?
If, after sintering, your gold ends up flaking or peeling off, there are two common culprits:
The paste was too thick. Keep your coats very thin. As a guideline, the paste should have a consistency like whole milk, not heavy cream.
The piece wasn’t clean enough. Dust or oil can prevent the paste from properly sintering. If your piece is fresh from the kiln, this should not be a problem (just avoid handling it by anything other than its edges). If your piece has been sitting around your studio for a while, clean it with denatured alcohol before you begin.