Spidery Spectrum bubbles - manufacturing defect?

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Gail Bunt
Posts: 17
Joined: Mon Feb 02, 2004 7:35 pm
Location: Saskatoon, SK Canada

Spidery Spectrum bubbles - manufacturing defect?

Post by Gail Bunt »

Bubbles have been done to death, but one more time ... .

I have been tack fusing small pieces onto a single layer of 3mm Spectrum. Wide, spidery bubbles form between the base and these little tack pieces. They raise welts on the tack that look like mistakes. This happens even with pieces 1" sq.

Spectrum recommends a slower ramp and a soak at 1220. I tried ramping at 200 and soaking at 1220 for 3 hours. The bubbles just sat there.

Some departed and some become round when held for 45 min at 1405 or 15 min at 1440. By that time the fuse had gone from tack to almost flat, though, which is not what I want.

There were large clear Spectrum bowls at a show on the weekend that were riddled with these spidery bubbles. The bumps gave the pieces a textured look that was interesting, but not what I'm after. Pieces done with BE had bubbles, but the bubbles were round and attractive and didn't raise welts.

Is there a solution short of fusing everything flat? Is Spectrum always this way? Am wondering whether to switch to BE before getting more invested.

Thanks to anyone who can bear to revisit bubbles.

Gail
Tony Serviente
Posts: 328
Joined: Thu May 29, 2003 11:48 am
Location: Ithaca,NY
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Post by Tony Serviente »

What kind of Spectrum are you using?
Gail Bunt
Posts: 17
Joined: Mon Feb 02, 2004 7:35 pm
Location: Saskatoon, SK Canada

Post by Gail Bunt »

Hi Tony,

All System 96. The dealer just started carrying fusible, so it's all new stock. Base is clear; tack is coloured cathedrals.

By the way, have used homemade kiln wash of kaolin + alumina and have used Primo; same result with both. Always bake shelves at 500 for 20 min. and let cool before using.

Gail
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