Wave Mold Slump Breakage

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clenzly
Posts: 3
Joined: Sun Feb 18, 2018 9:28 am

Wave Mold Slump Breakage

Post by clenzly »

I have been attempting to slump a pocket vase using a wave mold. The initial mold to create the pocket works fine. However, almost every attempt to slump it using the wave mold breaks. I've tried several schedules and have been unsuccessful. Do you guys have any ideas that might help me? The last schedule I used was based on the thickness of the pocket including the fiber paper used to keep the pocket from closing.
Test 5 schedule - slowed the ramp up and increased the soak time.
Seg Rate Target Soak
1 200 1250 10
2 * 900 180
3 100 700 00
4 * 100 00

The was the last schedule I used...slowed it down to a crawl (took 2 days)with the same result.
Picture of crack...All are similar
Picture of crack...All are similar
Seg Rate Target Soak E
1 50 1250 10
2 * 900 360
3 7 800 00
4 12 700 00
5 41 70 00
Mark Hughes
Posts: 46
Joined: Mon Mar 17, 2003 6:27 pm
Location: Omaha, Nebraska

Re: Wave Mold Slump Breakage

Post by Mark Hughes »

What is the thickness of each layer you are fusing? They look like single layers so maybe your annealing segment is too long. I don't think you need to add the thickness of your fiber paper, just the glass.
The cracks look unhealed, if this is correct then it cracked on the cooling segment.
Mark Hughes
JestersBaubles
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Location: North Logan, UT
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Re: Wave Mold Slump Breakage

Post by JestersBaubles »

There is no such thing as "too long of an anneal" and since the fiber paper will insulate the glass, you need to adjust your ramp up. I would try 100/hr. If you are holding three hours at 900 deg, the annealing should be sufficient.

Dana W.
JestersBaubles
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Re: Wave Mold Slump Breakage

Post by JestersBaubles »

Upon a second look - is that System 96 glass? If so, your anneal temp should be 950.

Dana W.
clenzly
Posts: 3
Joined: Sun Feb 18, 2018 9:28 am

Re: Wave Mold Slump Breakage

Post by clenzly »

I’m using Bullseye glass. The top portion is one layer. The bottom portion is 2 layers with 2 layers of fiber paper used to make the pockets.

I don’t have an issue when I create the pockets. Just when I try to slump. The issue seems to be where the single layer meets the double layer. That’s normally where the break is.

I tired annealing for 6mm and it basically split into 3 pieces.
clenzly
Posts: 3
Joined: Sun Feb 18, 2018 9:28 am

Re: Wave Mold Slump Breakage

Post by clenzly »

I will try the slower ramp uo
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