WarmGlass.com

I've tried everything short of sandblasting and fire-polishing but have not been able to completely remove marks left behind by the 'System 96' label and some little circular, colour-coded stickers I applied to the glass for quick identification of off-cuts. (I have 90 & 96 and don't want to make any silly mistakes).

The labels have been on for some time during several long, hot summers.

So far I've tried: Windex, dish soap, hand soap & nail brush, acetone, isopropyl alcohol, vodka, Reusche stainer powder, methyl hydrate, bi-carb soda and bad language.

The marks left behind do not appear to be adhesive residue. The glass is perfectly smooth to the touch and shiny. The marks are not easy to see. The glass has to be tilted towards the light 'just so'. At the right angle the ghosts of the rectangular label and the little circles are visible. I've searched the archives but can't be asking the right question.i.e. 'Remove label residue' '& Remove sticker residue'.

If I can't get rid of the ghosting I may turn it over and paint on the back, instead. It's very smooth too but has very slight texture I could tolerate better than risk the label shapes emerging through the painting.

Has anyone else had this problem? I hope there's an easy fix I haven't tried yet. The glass is Pearl White Opal, a System 96 colour I don't see currently listed, but it is several years old.

I'd appreciate any suggestions. Jen

Paint thinner and lacquer thinner are my favorites. Lighter fluid if you have it also is very good. Very high evaporative rate.

Jim "The Hobbyist"

Surprising. The gawd damned stuff should have submitted to the mf-ing acetone. Jim recommended petroleum based solvents, that's a good idea but most residues that dissolve in mineral spirits will also dissolve in acetone. Acetone or lacquer thinner work on all the tapes and stickers I encounter. Try maybe something from the bathroom tile lime cleaner department. An acid. or use abrasive and fire polish the shit.

Surprised acetone didn't do it. And bad language seldom works, but it does make you feel better. About the only other thing I can think of is CLR (Calcium Line Rust), which has multiple solvents but may not be available in Australia.

On the other hand, the company that put that sticker on has gone out of business, though I doubt if that's consolation.

Whiting.
Also have to remember that the opal glass with the problem is by its very nature a devitrified glass.
Once devit has started as in the glass was devitrified to create the opalescence, it is more subject to other things that may devitrify it like the stickers or even glass sucker ring marks.
If the whiting does not remove it, basically you are done and have to live with it and or sandblast it off which in turn causes more ability to further devitrify during a firing process.
It is why opals are more sticky to kiln shelves.
It is also another reason to use Bullseye with its higher COE and harder/stiffer/more controllable nature.

Most of the suggestions offered seem to be related to sticker glue removal (eg: paint thinner, lacquer etc.)... not the "ghosts" you describe. I have experienced the ghosts you refer to when I have removed a small pricing label after it has remained on a piece in my studio for some years. I think the chemical in the adhesive has altered the glass surface over time. Unfortunately, I have not been able to alter these "ghosts" . They are mostly seen only when on a white surface and tipping piece to see it. I do know that if refired the ghosts disappear . Sorry I don't have the magic answer.

possibly buff with a little pumice or cerium oxide. they will actually polish the surface.

Sprinkle some Bon Ami cleanser (it's finely ground limestone) on the surface, add a little water and rub. Like Cerium Oxide, it will polish the surface removing any residue.

Tony

I think the ghosts occur similar to how you make glue-chip glass: spread hot hide glue on glass, then as it cools it rips the surface a little. I think the ghosts are where particles of the adhesive dried and disrupted the shiny surface by pulling at it. idk. I've had same experience - they pretty much fire polish off. Would be a real drag if you did stained glass and had no kiln to polish them off . . .

Great idea Tony. BonAmi being limestone is the same stuff as whiting which is calcium carbonate which is limestone.
Seriously the best glass cleaner going for the price.

Thanks so much to everyone who replied.

After posting my original question and having already tried a WGB search with no success I posed the question to Google and this 2014 thread, from WGB, came up, with some similar replies:

http://www.warmglass.com/phpBB3/viewtop ... ls#p350770

As it is a 'ghosting' problem rather than adhesive residue, which solvents remove, I'll try calcium carbonate, which I have, and if that doesn't work I'll buy a Magic Eraser. The most abrasive product I've tried so far has been bi-carb. (baking soda). As Don commented that firing removes them maybe that's the next step, to pre-fire the glass before painting it.

And Kevin, I have both BE and Spectrum because I live close to the largest Spectrum wholesaler, probably in the southern hemisphere, where I can buy full sheets. The full sheets of BE I have were brought with me from North America. BE here can only be shipped in 12" x 12" sheets, unless one buys a crate of it. Thank you for the devit. explanation regarding opalescent glass.

Can someone suggest the minimum temperature that might remove them, please? I don't want to take the chance of painting without pre-firing then finding out that the marks are there, spoiling the painted finish. Thanks again for all the suggestions.

EDIT:

Thanks, Tom. I do have cerium oxide and the buffing wheel, will search for that, too.

DonMcClennen wrote: I do know that if refired the ghosts disappear . Sorry I don't have the magic answer.

Calcium carbonate didn't work, or I didn't rub it for the requisite number of months.....and I can't find the buffing wheel for the cerium oxide treatment.

I'd like to try firing the 'ghosts' off. Don, or anyone who knows, what's the minimum temperature that would work, please? As it will be a single layer I don't want to distort it.

Thank you, and happy new year to everyone!