sudden, mysterious 'film' on glass

[Bonnie Rubinstein]

wow- this has me stumped!

can't figure this one out.. on one of my favorite flat wall pieces, a film appeared (glass was fused a few months ago!)

I can't remove it! Not with Windex, vinegar, paint thinnner, muriatic acid..you name it, it is 'ingrained ' in the glass . Like white brushed areas.

I do not have a clue where it came from..the glass was just in my studio, along with my other art.

I wonder what to do, and if just applying Spray A and bring up to 1350 might help. (These are several tack fused elements, so don't want to go higher.

Any ideas???

Thanks!

[Bonnie Rubinstein]

in thinking about this, it almost appears that I wiped the glass with a rag that corroded it.. the rag may not have been clean...

are there any chemicals in a typical fusing that, when accidentally combined, corrode or leave a residue on glass that is hard to remove?? I.e. alcohol, windex, etc?

[Bert Weiss]

First, windex is evil. Never use it on glass. (that Greek wedding stuff, maybe)

Try washing the glass with muriatic acid. If the source of your scum is alkaline, this will neutralize it.

I once fired a glass desktop on woven silica cloth. It had a killer scum on it. I remade the piece, and planted the reject outdoors in a garden. A year later I noticed that the scum was gone. Acid rain had eliminated it.

[Bonnie Rubinstein]

I did try the muriatic acid..nothing.

As I said, the scum appeared months after the art was completed, and perfect! so, this is very worrisome.

Maybe.... there was a paper towel in the studio with expoxy on it..and perhaps I picked it up and wiped the glass with it to clean it.

[Kevin Midgley]

You've got glass disease in the traditional Blaschka format. The glass, whatever you used in it will continue to atmospherically corrode and eventually fall apart. Might take a few years but the piece is a toast.

[Tom Fuhrman]

I think the proper term for it is bloom. glass formulation had too much alkali in it and eventually it corrodes. I've had several antique pieces that sat in the display case for years and when removed had a film on them like they had sweat on them, when wiped on your hand they smelled like rotten eggs. I heard Dominik Labino give lecture on this many years ago at a GAS conference. I was at a factory in WV one time where most of the ware in their showroom was starting to do this, I couldn't believe they were selling this stuff.

[Bonnie Rubinstein]

I don't think that is the issue. I use system 96, and the only bloom on my glass, I believe, (now that I have played thought extensively about this for 48 hours), is residue epoxy on a rag that I might have used. It is the only explantion I can think of.

So, I will try a product called MEK, but I believe the epoxy streaks are bound into the glass. Then may fire ith Spray A.

Thanks for the input.

[Warren Weiss]

Bonnie,
If you use Spray A you have to go to a full fuse to get it to flow and glaze. That will flatten the glass.
Warren

[Mary Lou]

Bonnie, although your piece is perfect, could you sandblast it, then reslump which would give you a matte finish?

[Mary Lou]

Picked the following off another site. I thought Spray A worked at a lower temp the Super Spray, so maybe might work. If it does flatten, could you reslump?

Hotline Spray A Plus
by Hotline

The original popular Spray A has been reformulated and is now 100 percent lead-free. It is a clear, low melting glass, ground to micron size and suspended in a medium, suitable for brush or spray application.

Spray A may be applied to fusing projects when ready for firing to prevent devitrification on the glass surface, or as an overglaze for dull or matte surfaces, or even previously devitrified surfaces.

Fire to minimum 1300 degrees F (704 degrees C).

[Mary Lou]

You've got glass disease in the traditional Blaschka format. The glass, whatever you used in it will continue to atmospherically corrode and eventually fall apart. Might take a few years but the piece is a toast.

Kevin, I checked Blaschka in Wikipedia and did not find anything referring to glass disease. It did mention the plants being pollinated or diseased in some way.

[Bonnie Rubinstein]

I do use Spary A on a regular basis. I was wondering if the steaks on the glass, which might be a chemical bonding of epoxy into the surface, would be eradicated by Spray A.
The pieces is flat, so slumping isn't an issue. But I don't want to ruin the tack fused elements by refiring too high. So, 1300 is good.

[Warren Weiss]

Bonnie,
The tack fuse is what I was referring to a being lost, not the slump (which would also be lost at full fuse.) I don't think any oversprays will glaze over (become shiney) at 1300, but if anyone else has experience at that temp. let us know.
Warren

[Bonnie Rubinstein]

The specs on Spray A Plus say "fire to a min. of 1300". Although usually go to 1370, to fuse, I hope this time the 1300 will be sufficient for Sray A to do its magic.

[Kevin Midgley]

http://en.wikipedia.org/wiki/Glass_Flowers Restoration section.
Chemistry of glass was wrong.

[Buttercup]

Bonnie, I don't have the experience of the other people who have responded but the first thing I'd try would be Mary Lou's suggestion to sandblast with a fine grit, 220 perhaps, then if you don't want to fire polish, use diamond pads to polish or bring to a satin matte finish. Morganica often mentions this. Good luck with it, Jen.

[Rick Wilton]

http://en.wikipedia.org/wiki/Glass_Flowers Restoration section.
Chemistry of glass was wrong.

I like the line about the cracks caused from vibrations in the building. I think it's a bit more of a problem than vibrations causing the cracks.

[Bonnie Rubinstein]

I can't hand polish, as the elements I tack fused on are many, and shaped in a way that would make it impossible. And I am looking for high gloss.

I will attend to this when the blizzard we are having (so far, easily a foot of snow in one day), subsides. I will post results then.
Keeping my fingers crossed. will try MEK to dissolve the scum (epoxy?), and then will use the Spray A plus.

Moral of the story. ONLY keep clean rags on your working tables!

thanks for all the support, (and stories of glass diseases), everyone!

[Kevin Midgley]

It will only return. there is no cure for glass disease other than starting over using compatible glass.

[Bonnie Rubinstein]

I used only system 96. Everything was compatible. So, the only disease I was dealing with was my own lack of discarding a contaminated towel that I used to clean the glass. Never again.

each day is a learning experience in a glass studio.