Can I fix devit on tack fused tekta with powder?

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sheila
Posts: 13
Joined: Wed Apr 02, 2003 2:03 pm
Location: Seward, Alaska

Can I fix devit on tack fused tekta with powder?

Post by sheila »

I'm back to fusing after several years and I see that folks have devit issues with tekta on thin fire. Wish I'd known. I've tack fired 2 same size pieces for a split window in a door. Both have compatible colored pieces on 3 mm Tekta clear, fired on thin fire with 1/4" fiber surrounds to maintain footprint. Pieces about 14"x20", using same glass, same handling, same firing schedule. First window came out perfect. Second has devit area about 1.5" by 12" close to the center.
Very perplexing.
Question...is it possible to refire to 1375 with a sprinkling of clear powder to maintain contour and achieve fire polish? I'd think it would require a hotter temp, but would sure like to hear otherwise! First firing schedule held for 12 minutes at 1375.
If this is an option....I assume I should sprinkle the whole darn piece and not just the devit area. Yes?
Brad Walker
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Re: Can I fix devit on tack fused tekta with powder?

Post by Brad Walker »

It would require a hotter temperature. You have got to get hot enough to shine up the layer of powder, most likely 1400F or higher.

And, yes, if you did you'd want to apply powder to the entire piece, not just the problem area. Only one or two grains thick of powder, more and you risk cloudiness from bubbles between the grains of powder.
Kevin Midgley
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Joined: Mon Mar 10, 2003 11:36 am
Location: Tofino, British Columbia, Canada

Re: Can I fix devit on tack fused tekta with powder?

Post by Kevin Midgley »

a light sandblasting of the entire surface could remove it as well as provide a slightly textured look to the finished window after firing.
Some of your devit could also have come from not drying out your kiln before firing.
Moisture can do weird things.
Particularly ocean moisture.
It is cured by heating your kiln before use to 1000F, allow it to cool and then load and fire.

There's also no free lunch on kiln preparation. Kiln wash is the time proven material with the lowest chance of problems. (and cheapest)
Bullseye's kiln wash is softer, with less clay binder than some of the other favorite brands. If it should stick it should be easier to remove than higher clay brands.
Important! Rub your bare hand once! over the surface of the prepared shelf before firing. The fine powder you release from the Bullseye kiln wash sits on the shelf and helps to act as a separator.
It will also, depending on the firing temperature provide an even slight texturing to the glass surface.
Welcome back.
sheila
Posts: 13
Joined: Wed Apr 02, 2003 2:03 pm
Location: Seward, Alaska

Re: Can I fix devit on tack fused tekta with powder?

Post by sheila »

Thanks for your comments. So many variables to consider and sometimes there are just surprises…good and bad! With closer scrutiny the devit is on the flat side of the piece so it’ll require a redo. Now whether to try it on thin fire so the back is texture free like the 3 pieces that complete the window design!
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