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low fire underglaze pen:

updated sat 8 nov 97


Fred Paget on fri 7 nov 97

In my experiments with laser toner images on bisque ware I was never able
to find a clear glaze that would not remove the image in the glaze firing.
This suggests a possible solution to your problem. A light iron oxide
marking ( which is what the laser toner leaves when fired) will dissappear
almost completely when glazed over. You could experiment with an iron
solution such as 2 percent ferric sulfate or a weak suspension of very fine
iron oxide stain (or laser toner?) and put it on with a pen. This should
leave a light iron oxide mark when fired.You want it fairly faint or it may
not burn out in the glaze. Try it out and let us know if it works.

"bbb!aaa" (no other identity) wrote:
> Our studio is in need of a low-fire glaze pen or marker that will fire
>out at a low cone for organizational purposes. The demarcation of a class
>session, though unsightly, has become seemingly necessary to attempt to
>organize a great deal of pottery (and different signatures)
>at a reasonable pace. An ideal pen would be able to leave a class "symbol"
>without damaging the pot with marks during the greenware phase and still be
>visible after being bisqued. Hopefully, this mark will burn out after the
>glaze firing. We high-fire to cone 6 in an electric kiln--I am unsure of
>our bisque temperature....Any suggestions?

Fred Paget---Mill Valley,CA,USA
Never try, never win!