Another particularity of silver stain is that it is usually painted on the underside of the glass, and when fired, it is fired with the silver stain against the kiln shelf, rather than facing up. There are a few reasons for this. One is that silver stain is done after the tracing black and matte, and if paint the silver stain on top of the tracing black and matte, the colored clay residue melts into the tracing black and matte and leaves an unattractive dull finish and a colored cast. Another is that placing the tracing black and matte side of the glass against the kiln shelf will cause the paint to fuse with the kiln wash, leaving ugly marks on your art work. Furthermore, this fusion with the kiln wash will cause uneven contraction/expansion of the glass during firing greatly increasing the risk of cracking.
If you have used a kiln shelf with silver stain face down, you MUST remove the kiln wash, and apply a new layer after the firing. This is because, as said earlier, the silver stain itself is invisible. There may be a lot of it seeped into the kiln wash. You would not see it. But next time you fire something on that shelf, the glass WILL PICK UP the invisible stain, and stain your piece with unwanted yellow.
REMINDERS for SILVER STAIN:
- Paint on underside of design.
- Fire with the black & matte side UP, and the silver stain side DOWN.
- Don't panic! You must wash off the clay matrix after firing to see the actual results.
- Remove old kiln wash and re-apply freshly on shelves touched by silver stain.
- Silver stain is corrosive to metal over time. You will need a dedicated mixing knife.
- Brushes used for silver stain must be thoroughly cleaned after use. A foaming shampoo will help remove silver stain from the hair yet be gentle on your brushes.
Silver stain fires lower than tracing black or matte, the same temperature range as enamels, 1050-1080F. However, silver stain can actually fire as high as 1250F without adverse effects, so it is sometimes a matter of convenience to fire your silver stain along with a batch containing tracing black and/or matte.
Silver stain is very temper mental, and results will vary with the type of glass you are using. Artists working on large projects will perform tests, but those working on small pieces may just take their chances. Although some silver stain is advertised as vivid orange, be prepared to be disappointed with the results being the usual yellow, quickly darkening to ochre (almost in a stepwise, binary fashion) if applied especially thick. This darkening is difficult to control and rather unpredictable.
One trick to make the silver stained areas more lively is to apply the stain twice, with two firings. This way, you have considerably more control over the various shades within your yellow/amber range, can achieve deeper colors without stepping up to ochre. As yellow covers a very narrow range of wave length, making the effort of including many intensities within it is very rewarding to the eye.
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