Solution for devit on irid

[JestersBaubles]

I would like comments on how to resolve a devit problem I have on a piece.

The piece is a strip construction (sys 96)-- 1/4" pieces standing on edge on a full sheet of clear irid, with the irid size down. There is a "smathering" of devit across one whole side. Hopefully, I can post some photos from a Flickr photostream:

(OK, I edited this thing about 10 times and finally got the photo -- I THINK!)

If the image doesn't work, just go to the darned photostream : http://www.flickr.com/photos/48008910@N ... hotostream

Not wanting to admit it was devit, I tried soaking & washing in soapy water. Then, scrubbing with a scrub brush bought just for this purpose. Then, soaking in CLR and scrubbing with the fancy new brush... to no avail.

What would you suggest? I don't have a sandblaster, but I could hand lap (my lap grinder isn't large enough). But I would not want to sand or lap, anyway, because the irid side is down and so the irid coating would be sanded off. The irid side is the back of the piece -- I was planning to slump it on a stainless S-mold. I placed irid side down because I wanted the texture -- it seems to increase the "sparkle" and color spectrum when viewed from the front.

I used hair spray during construction (cheap, unscented) -- there may have been excess on the strip pieces because I got it half laid out and decided the design was not random enough so I disassembled, washed, and started again. However, the pieces with hairspray would have been on top of the irid, so I don't think that is the problem. The other thing is that the piece was fired on top of Spectrum's Papyros. I am going to be darned unhappy if the use of the Papyros caused the devit. i have always used Bullseye Thinfire with great success (no devit, less texture than kiln wash). Of course, I just bought a big roll of Papyros, after having good results with several sheets I bought for test.

Thanks for any ideas you might have on resolving the devit!

Dana

[David Jenkins]

Which side is the devit on? If it's on the top surface, why would sanding/lapping it interfere with the irid on the bottom?

[Valerie Adams]

I don't work with Spectrum, so my experience is based on Bullseye, which has a warning in their (older) catalog that firing irid on Thinfire may result in splotchy, uneven irid. So, lots of different variables (glass, paper product), but I'm guessing you're seeing that result: uneven, splotchy-looking irid, not devit.

No way to fix, other than to remove the irid via sandblasting, that I know of.

Edited to add the mention on Bullseye's Thinfire technical sheet:
Applications: ThinFire has been used with excellent results in Bullseye’s factory studio for many types of fusing applications. However, it does not work in every application. The one example we have noted to date is this: used in direct contact with iridized glass, ThinFire may cause a reaction resulting in surface pitting.

Here's another link I found:
http://glass-suppliers.com/glass-proces ... -3223.html

[Brad Walker]

If it's on the bottom, it's not devit. Devit only occurs on the side exposed to air.

If you fired on thinfire, it's contamination between the thinfire and the irid (as Valerie notes). The photo looks like thinfire contamination.

If you didn't fire on thinfire, it's still contamination of some sort. Not devit.

The only solution I know of is sandblasting or grinding and even that's difficult. You have to blast pretty well to get all of the contamination off. And of course the irid coating will go, too.

[JestersBaubles]

Yes, irid side face down, touching the Papyros. I have fired irid side down on fiber paper (no problem, of course), and so I didn't even think about possible interactions. All of my other irid side down work has been fired on kiln washed texture molds or fiber paper, come to think of it.

Damn! I really like the piece, too. At least it wasn't devit -- I was going to be REALLY disappointed if I started seeing devit using Papyros, given that I have several hundred feet of the paper in my basement! I didn't think devit could occur on the bottom, but when it wouldn't wash off, that was my only thought.

So... I am considering options for "working with it". Possibly sand or etch a wavy-looking "swosh" across the back that covers the problem. I've also considered tack-fusing clear coarse frit... or, just sand the entire back, fire polish, and move on. I don't have a sandblaster, but maybe it's time to buy one.

I was hoping for a piece to go into our local gallery, but it might be another keeper.

Thank you for the feedback.

Dana

[Mark Wright]

A tid bit that is worth what you paid for it, but I am sooooo glad I finally broke down and bought a sand blaster. I love not only knowing what it can do, but knowing it is there when I need it.
A USU graduate now living in the warm south.

[JestersBaubles]

A tid bit that is worth what you paid for it, but I am sooooo glad I finally broke down and bought a sand blaster. I love not only knowing what it can do, but knowing it is there when I need it.
A USU graduate now living in the warm south.

Thanks, Mark.

I am originally from the South -- Huntsville, AL, but I have been here for nearly 24 years. I came out with someone getting his PhD and stayed. Time flies

Dana