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uneven edges

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uneven edges

Postby zenyen » Mon Jan 18, 2010 10:22 am

I am fairly new to fused glass so this may seem a silly question. I have been using the bullseye kiln shelf wash with great success from last spring when I started until this winter when I have had regular problems with the glass grabbing the shelf and leaving uneven/sharp edges as it shrinks back. I'm using a 13" Skutt with side coils and typically I use a slow full fuse most recently up to 1440 for some texture with a 20 minute hold.

I have wondered if it is the humidity - I live not far from Seattle and it has been terribly wet this year - I usually prep my shelves one day and fire the next day so they have time to cool and I have time to design.

Thank you,

Re: uneven edges

Postby marykaynitchie » Tue Jan 19, 2010 4:31 pm

Hi Rain,

What kind of glass are you using?

Can you describe how the projects are laid up in the kiln before firing? For instance, does your project consist of 2 layers of 3mm glass? (I am wondering if it is possible that your project's "footprint" is shrinking in area as it is fired.)

Mary Kay
Mary Kay Nitchie
Bullseye Glass Co.

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Re: uneven edges

Postby zenyen » Fri Jan 22, 2010 12:40 pm

hi mary kay, thanks for responding,

i am using spectrum 96 glass, mostly 3mm but some are 2 mm thick, and i'm hammering pieces of clear coloured glass into 1/2 - 1" pieces that are being poured onto the shelf. thus some areas are 1 layer and some are multiple layers - obviously the glass often has uneven edges, but that has been consistent since i started to play with the glass this way

what do you mean by the footprint? do you mean the overall size?

Re: uneven edges

Postby ilmcreations » Fri Jan 22, 2010 2:47 pm

Hi, the pointy spikes often get created when there is a bit too much heat, or when heat is applied too long (worse if both) especially when you do not have enough thickness in glass prior to firing. It will make it shrink unvenly and creates those painful spikes.

Re: uneven edges

Postby KarynReott » Sat Jan 23, 2010 7:44 pm

Anytime you have only 1 layer of glass you will be more likely to have the glass pull in and leave spikies, especially if the final processing temp is high.

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