Drop ring issues

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aliceRI
Posts: 39
Joined: Wed Aug 03, 2005 8:53 pm
Location: East Greenwich, RI
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Drop ring issues

Post by aliceRI »

So, I am in the process of making a fused glass font bowl for my church. They want the opening to be 12" with a lip and 6" deep. I have purchased a drop ring from Laurie Spray along with a 18 1/2" steel ring. I figured 3" overhang would be enough to hold. Laurie's rings have a lip on one side to help have the glass remain on the ring and NOT fall through. I also was nervous so I ordered a 20"metal ring from slumps, just in case I don't have a big enough lip to go by.
Anyway, attempt #1, I went too fast (200º/hr on 1st ramp to 1200. I also used the kiln that does not allow top elements to be turned off. Major fail.
Attempt #2, new, larger kiln (Olympic) that allows me to keep top elements off, Scheduled ramp at 150º/hr to 1200 and hold for as long as it takes. Kept peeking every 5 minutes, after 1 hour, glass had fallen through. This practice piece was 15" with only a 1 1/2" gap around to hold the rim. The glass lasted for 45 minutes before it sunk to the floor. (they want it 6-7"deep. I may settle for 4-5")
Attempt #3: Olympic kiln with top elements turned off and piece center in kiln, raised 7" from shelf. This piece of glass is 20" and 9mm thick. My schedule:
50 - 1100 - 45
50 - 1200 - As long as needed (was going to program 2 hours and delete the after peeking every 5 minutes.
once reached AFAP - 900 - 2:00
150 - 750 - off

The 20" circle should give me enough lip to hold the piece in place, right? Any suggested are greatly appreciated.
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