Page 1 of 1

dichro problems - Wrong glass cleaner

Posted: Sun Jun 03, 2012 2:07 am
by Jill
So I did a firing a few hours ago of dichroic jewellery, and when I took my first peek during the firing(around 1000), all the rainbow 96 CBS was peeling. Then I noticed that almost all the dichro in the kiln was looking as if the coating was breaking into "sparkles". This all from sheets of glass that I've cut and fired from before without any problems. There were a couple of pieces of 90 in a pinkish rainbow that also were peeling.
After thinking long and hard about what I had done differently, I realized that I used a new glass cleaner, a biodegradable one. Also there was a slight burning smell during firing that I hadn't smelt before.

Before today I had used the same ammonia free glass cleaner for many years (just ran out) and only had this problem a few times, but with scraps of unknown origin, often Rainbow,patterns in Pink/Teal, and a baby pink glass - in those cases I believed that the glass itself was the issue. Have even used used regular Windex a few times on dichro and black glass without problems.

Kiln is not cool yet, but except for the clear capped stuff, all the Rainbow glass will probably be jumked. The other colours, I will have to touch and see if the coating is rough or not....maybe some can be saved with a thin clear cap. Most of the glass was etched with pictures, so I hate to loose all that work.

So I post this as a warning to Newbies. And if any of the regulars here have suggestions on future glass cleaning, (products, methods), I would appreciate it.

Re: dichro problems - Wrong glass cleaner

Posted: Sun Jun 03, 2012 7:22 am
by Jeanne
I only use coe 90. I generally just clean my glass with water and dry with a paper towel (and make sure no visible spots or imperfections or lint) before firing. Never had a problem. 9 years doing this (and that includes a lot of dichro). My guess it's as you suspect - your cleaner. The only glass cleaner I do use is GlassPlus. But that's usually if the sheet is a little dirty and I clean it before cutting. Pretty sure that gets rinsed off from grinding and wiping off the water on the glass.

Re: dichro problems - Wrong glass cleaner

Posted: Sun Jun 03, 2012 5:09 pm
by Lynn g
I'd suggest you contact CBS tomorrow. It may be that you had some defective glass (it happened to me once).

Re: dichro problems - Wrong glass cleaner

Posted: Mon Jun 04, 2012 12:01 pm
by Valerie Adams
I've occasionally had a scrap of dichro that has had sparkles burst off.

I simply can't imagine that a glass cleaner (any residue of which would burn off way sooner than the glass was softened) would be powerful to break the dichro coating's connection to the glass.

Like Lynn says, call CBS.

Re: dichro problems - Wrong glass cleaner

Posted: Mon Jun 04, 2012 2:26 pm
by Morganica
I think that if a glass cleaner could cause a chemical reaction that detached dichroic coating from glass, especially a biodegradeable one, a lot of fusers would be in trouble. ;-)

I think it's more likely that a section of the dichro sheet has problems--possibly the glass was contaminated when the coating went down, for example--and agree that you should call CBS. Save samples of a good fusing with that same sheet, as well as the defective samples, and let them take a look. In the meantime, use another sheet and see if it does the same thing.

If it turns out that the cleaner *is* the culprit, it would be helpful to post which cleaner you were using.

Re: dichro problems - Wrong glass cleaner

Posted: Fri Jun 29, 2012 11:54 pm
by Jill
Most of the pieces worked out, though the coatings felt a touch rougher than normal. A few were really rough and unsellable, but only in the Rainbow. There definitely was splintering, because a couple of thin splinters went up in the air and landed on top of adjacent clear capped pieces.

The burnt smell was probably from the cleaner, but I think everyone's comments are correct, in that it was the glass that was the culprit. Still I will be using water, or another ammonia free cleaner in the future.

This was from a 1/4 sheet of 96 CBS Candy Apple Stripe A that I got from DichroicInc. ...I'm too small time to order from CBS directly and usually get 1/4 sheets.
This is the only sheet I have to work with, except for some scraps that I pick up from time to time in both 90 and 96.
Monty is awesome to talk to, very knowledgeable, he said that Rainbow is one of the glasses that can be prone to these kinds of problems.

I'm in Canada, so don't know if this is worth shipping it back to the USA, but Monty says they do take returns on glass, and is always willing to send me chips and samples of things I'd like to try. So I think I'm just going to be careful not to fire too high, and clear cap most pendants that I make out of this sheet.

While talking colours with Monty, I just found out that the RSB on black that I was never happy with is an miscolour/exotic, which is why it is mint green instead of light blue. I've had this sheet since 2006, but didn't get around to firing it until last year. I didn't realize that RSB is actually suppose to be attractive!

Re: dichro problems - Wrong glass cleaner

Posted: Sat Jun 30, 2012 5:15 am
by Lynn g
You can also try firing it dichro side down; that's one of the suggestions Monty gave me, and it worked.

Re: dichro problems - Wrong glass cleaner

Posted: Sat Jun 30, 2012 8:00 am
by Jeanne
A few years back I contacted CBS directly about some Dichro I had bought from my supplier. It was patterned dichro and the pattern did not survive the fusing and looked like mud. They sent me a replacement piece. I provided pictures in my email.