broken glass

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AJK25
Posts: 41
Joined: Wed Jul 20, 2005 12:49 pm

broken glass

Post by AJK25 »

I am having some issues with broken glass. I make cabinet knobs and handles. I introduced a new collection of hardware in January. I have probably made 1000 pieces of hardware since then, and recently 4 of them arrived at the customer with broken glass. I don't think it was because they were bounced around during shipping, as we pack them very well with bubble wrap. I think it had to do with the way they were fused. We have two styles -- one is 6mm Bullseye clear glass, and the second style is 6mm clear Bullseye glass layered on top of 3mm Bullseye white or gray glass (for a total of 9mm). We fuse them 400 degrees per hour to 1000, no hold. And then AFAP to 1370, no hold. And then AFAP to 960 (recently changed to 970) and hold for 1.5 hours (anneal). And then 75 per hour to 750 and turn off kiln. Attached are two photos of broken pieces. You can see that we have holes drilled into the glass (before fusing), and we use a screw to attach the glass to the metal base. We do not screw the screw in very tight, as we use glue to hold the screw in place. In fact, with the handles, we intentionally do not screw it in all the way, so there is not any pressure from the screw on the glass. Photos of broken glass attached. Would appreciate any help.

Thanks,
Drew
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Brad Walker
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Re: broken glass

Post by Brad Walker »

Doesn't look like a fusing issue to me. More likely handling of some sort or something heavy dropped on the place where it broke.

Be interested to hear what others think.
Marty
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Re: broken glass

Post by Marty »

Blunt force. Even incompat doesn't look like that.
AJK25
Posts: 41
Joined: Wed Jul 20, 2005 12:49 pm

Re: broken glass

Post by AJK25 »

Thank you both for your thoughts. The reason I had thought that it might be a fusing issue is because we pack these up extremely well when they ship out...bubble wrap, and then lots of padding in the box. It seems so unlikely to me that it could have broken during shipping. But I certainly could be wrong.
jim simmons
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Re: broken glass

Post by jim simmons »

Was the package damaged in any way?
Coud also be that the customer broke it and wants a replacement.
I have had that happen to me once.
The other Jim
AJK25
Posts: 41
Joined: Wed Jul 20, 2005 12:49 pm

Re: broken glass

Post by AJK25 »

Good question. I'm not sure if the package was damaged. I understand that the breakage may not be due to my firing schedule, but do you all think my firing schedule is ok? Am I annealing long enough? The pieces I'm firing are either 6mm or 9mm thick. Some are 1.25" square and some are 5" x 1.25"
AJK25
Posts: 41
Joined: Wed Jul 20, 2005 12:49 pm

Re: broken glass

Post by AJK25 »

I just received another broken handle from a customer. I;d love to mail one of you a sample of the broken piece to look at. I have no idea what is causing this breakage, but there have been five pieces that have broken, so something is definitely going on. Would anybody be open to taking look at one of these and possibly offer me some assistance? I'm somewhat worried, as this is a new line of hardware for us.

Thanks,
Drew
Marty
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Joined: Mon Mar 10, 2003 3:58 pm
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Re: broken glass

Post by Marty »

sure- I'll pm.
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