1 inch fuse

Carol B · Post by **Carol B** » Mon Feb 02, 2004 10:21 pm

Last night I full fused 4 tiles that are two layers of glass. Tonight I placed them one on top of the other (1 inch total thickness) and am going to attempt a tack fuse. My goal is to create a candle platform.

My schedule is

280 degrees/hour to 800 degrees and hold 5 minutes
500 degrees/hour to 1325 degrees and hold for10 minutes
Flash vent to 960 degrees and hold 40 minutes
175 degrees/hour to 800 degrees and hold for 10 minutes
Shut down to cool to room temp

I have heard more than once on this forum that opening the kiln is much like Christmas morning. I hope I do not find coal in my stocking tomorrow.

Carol

jerry flanary · Post by **jerry flanary** » Mon Feb 02, 2004 11:23 pm

What size are the tiles? What kind of glass?
so you are holding at 960 for 40 minutes and then dropping to 800 in less than an hour. I know a lot of casters skimp on the soak (the 960 hold) but that 1hour drop to 800 seems kinda short. without knowing what kinda glass, I would go 4hours from 960 to the bottom of your annealling range (700?) and then 4more hours to about 250 then off and natural cool. But I am not a caster, I just post over here to work on my typing skills.
What's the big rush anyway? Everyday is freakin christmas.

Amy Schleif-Mohr · Post by **Amy Schleif-Mohr** » Tue Feb 03, 2004 1:06 am

To help you we need to know what glass you are using. If it's BE you should take a look at their annealing thick glass chart. You are going WAY too fast.

Amy

Carol B · Post by **Carol B** » Tue Feb 03, 2004 9:52 am

jerry flanary wrote:What size are the tiles? What kind of glass?
so you are holding at 960 for 40 minutes and then dropping to 800 in less than an hour. I know a lot of casters skimp on the soak (the 960 hold) but that 1hour drop to 800 seems kinda short. without knowing what kinda glass, I would go 4hours from 960 to the bottom of your annealling range (700?) and then 4more hours to about 250 then off and natural cool. But I am not a caster, I just post over here to work on my typing skills.
What's the big rush anyway? Everyday is freakin christmas.

I used BE glass and followed the schedule recommended by my Skutt owners manual. I peeked this morning and so far so good, but then if my annealing was too short I may not find out for a while.

Carol

Carol B · Post by **Carol B** » Tue Feb 03, 2004 9:53 am

Amy Schleif-Mohr wrote:To help you we need to know what glass you are using. If it's BE you should take a look at their annealing thick glass chart. You are going WAY too fast.

Amy

I will check out the chart. Thanks.

Carol

Carol B · Post by **Carol B** » Wed Feb 04, 2004 2:36 am

The fuse is out of the kiln and a wierd thing happened. 3 of the layers tack fused nicely but one layer did not fuse at all. There is a small indent where the glass started to soften.

I have no idea why this occurred

Carol

Barbara Muth · Post by **Barbara Muth** » Wed Feb 04, 2004 9:35 am

My guess, you had a lot more mass to heat and that last layer didn't get hot enough for the tack fuse.

barbara

Carol B · Post by **Carol B** » Wed Feb 04, 2004 11:17 am

Barbara Muth wrote:My guess, you had a lot more mass to heat and that last layer didn't get hot enough for the tack fuse.

barbara

The layer that did not fuse was the one resting on the shelf. It was also the largest layer. About 4 1/2 inches square.

Carol

Bob · Post by **Bob** » Wed Feb 04, 2004 12:35 pm

Hi Carol,

Yup, Barbara is right ... need a longer soak at 1325 to allow the heat to seep into the center parts of the glass. For the thickness you mention I would soak it at least an hour. Glass is a poor conductor of heat. It takes a long time for heat to work into the piece, and a long time for it to conduct out when cooling. I always think of the bead workers holding onto a glass rod with bare hands. The glass might have been in the flame for 15 minutes and the flameworker can still hold the rod about 6 inches down from the hot end. Try doing that with a copper pipe.

And Amy's suggestion about using the Bullseye schedule for thicker glass is excellent. Your piece is likely to break because of the quick annealing time. Did the bottom layer not fuse on ... or did it crack along the surface during cooling? Are there any sharp edges in the bottom layer that were not there prior to firing?

Fuse it again... an excellent way to advance is experimenting.

Cheers,

Bob

Carol B · Post by **Carol B** » Thu Feb 05, 2004 10:56 am

Bob wrote:And Amy's suggestion about using the Bullseye schedule for thicker glass is excellent. Your piece is likely to break because of the quick annealing time. Did the bottom layer not fuse on ... or did it crack along the surface during cooling? Are there any sharp edges in the bottom layer that were not there prior to firing?

Fuse it again... an excellent way to advance is experimenting.

Cheers,

Bob

Hi Bob,

There was no cracking there was just a gentle indentation on the surface of the bottom layer. I will give is another try slowing waaaaaaaay down. I really appreciate the encouragement.

Carol