troubleshooting discolorations

[MarlaS]

a friend's firing some pieces for me -- all BE compatible glass -- & in a kiln w/ pieces from several people (getting glass from the same source & sometimes the same sheets), mine are the only ones that are developing discolorations --- she says it looks like blackish & goldish crud trapped between layers (layers usually a cathedral irid w/ clear/stringers sheet on top, or clear base under various other layers). i can get specifics on kiln & firing schedule, but the problem's specific to only my stuff. all pieces are fired either on paper or coated shelves -- i have the problem w/ both surfaces.

i use regular blue windex to clean my glass, & elmers straight from the bottle (don't use a brush) to hold pieces together during transport. my hands get washed w/ reasonable regularity. is there something else glaringly obvious i'm not considering? (& what else would be helpful to know???)

thanks,
marla

[charlie]

don't use windex. use plain water, distilled if you have hard water.

[MarlaS]

thanks charlie. you think it's the windex, or can it do other stuff to the glass?

[Jackie Beckman]

Also, it could be from the trapped elmers. You really should water it down, about half and half, and even then only use a tiny amount.

[MarlaS]

that seemed obvious to me jackie, except that it doesn't happen w/ each/every piece, even when the elements are similar -- that is, i could have 2 pieces, each of similar size & w/ similar elements, & one gets the crud & one doesn't....

i had been watering it down, & got lazy. am now doing so again, & using more sparingly.

thanks...

[jim simmons]

Also, it could be from the trapped elmers. You really should water it down, about half and half, and even then only use a tiny amount.

Don't even use Elmers.
Instead, use Aleen's " tacky" glue. It burns off cleaner that elmers and sets up a lot faster.

Jim

[MarlaS]

jim, do you water it down, or use it straight from the bottle? & do you find that you need to use it sparingly?
thx

[charlie]

i use klyr-fire straight. in order to tack down frit or small pieces, and if i'm going to use anti-devit, i just use borax spray, which seems to glue everything together anyway once it dries.

[jim simmons]

jim, do you water it down, or use it straight from the bottle? & do you find that you need to use it sparingly?
thx

I use it straight from the bottle. No branch water for this guy
It is allways a good idea to use any glue/foriegn substance sparingly.
Jim

[Amy on Salt Spring]

Do you get the crud more often on pieces with opaque glass in them? I think glue, oils or whatever show up a bit more when there is opaque glass involved.
Amy
P.S. I always clean with water and use dish soap if the glass is really dirty.

[MarlaS]

only cathedral.

[Sara]

Marla,

you don't mention your friend's firing schedule. I've seen that type of discoloration when there is a fair amount of glue or debris and the initial ramp up is too fast.

also occasionally I've seen a stain that almost looks like rust, primarily on clear.

good luck,

Sara

[Cynthia]

I'd bet a grunfle that it's trapped carbon stain from the glue. It only happens occasionally because it's only getting trapped occasionally.

Don't trap the glue between glass, but rather use it at the edges of the pieces you want to anchor down...and...figure out if you can come up with a better glue option. I use Rave or Suave supehold hairspray in a pump. It burns off cleanly every time for me. I spray the base, place my glass and it sets up quickly. Maybe you could try some test pieces with hairspray and see if you get different results.

The windex would give you a mark that would look like streaks. Try good old soap and water with a good rinse and dry with clean cotton towels if you aren't happy with the Windex.

My other thought is that the firing schedule may be so fast that you are getting lamination before the glue is fully burned off. A slower schecule might help too.

[MarlaS]

nm