fusing float glass with copper screen

[Paul Renoud]

I'm stumped... . I sandwich 1/8 inch mesh (and finer) pieces of copper screen (two inches square with frayed edges) between two layers of 1/4 inch float 36 x 36 inches. On top I position 1 to 3 inch geometric shapes of 1/4 inch float, trying to stay away from the copper, but sometimes overlapping. I fuse this on a bed of 1 inch fiber blanket resting on top of a raised floor of four 20 inch mullite shelves which are supported by bricks above my kiln floor. My kiln is deep and has elements in the sides and on top. I fire to 1475, drop to 960 for 5 hours, then decend over 5 more hours to 700 and off. 9 out of 10 times they come out fine. 1 out of 10 they crack, often around the "chards" on top, like it's a compatability issue. I feel like I'm too close to the margins, somewhere. I'd like to know where, so I can figure out what to change. Paul

[Brock]

I'm stumped... . I sandwich 1/8 inch mesh (and finer) pieces of copper screen (two inches square with frayed edges) between two layers of 1/4 inch float 36 x 36 inches. On top I position 1 to 3 inch geometric shapes of 1/4 inch float, trying to stay away from the copper, but sometimes overlapping. I fuse this on a bed of 1 inch fiber blanket resting on top of a raised floor of four 20 inch mullite shelves which are supported by bricks above my kiln floor. My kiln is deep and has elements in the sides and on top. I fire to 1475, drop to 960 for 5 hours, then decend over 5 more hours to 700 and off. 9 out of 10 times they come out fine. 1 out of 10 they crack, often around the "chards" on top, like it's a compatability issue. I feel like I'm too close to the margins, somewhere. I'd like to know where, so I can figure out what to change. Paul

You're annealing too low. Try 1010 - 1030. Brock

[Tony Smith]

Paul,

Also make sure that the float glass accents that you are using on top are cut from the same sheet, or at least from the same case, size, etc... as the large pieces. Float is compatible with itself, and usually with other sheets from the same case.

Tony

[watershed]

Casting with the mesh, is fine IMHO.

Sorry I don't have more to add.
Greg

[Bert Weiss]

I'm stumped... . I sandwich 1/8 inch mesh (and finer) pieces of copper screen (two inches square with frayed edges) between two layers of 1/4 inch float 36 x 36 inches. On top I position 1 to 3 inch geometric shapes of 1/4 inch float, trying to stay away from the copper, but sometimes overlapping. I fuse this on a bed of 1 inch fiber blanket resting on top of a raised floor of four 20 inch mullite shelves which are supported by bricks above my kiln floor. My kiln is deep and has elements in the sides and on top. I fire to 1475, drop to 960 for 5 hours, then decend over 5 more hours to 700 and off. 9 out of 10 times they come out fine. 1 out of 10 they crack, often around the "chards" on top, like it's a compatability issue. I feel like I'm too close to the margins, somewhere. I'd like to know where, so I can figure out what to change. Paul

You're annealing too low. Try 1010 - 1030. Brock

Agreed. You are spending too much time at the wrong temp. Do a slump test (Lundstrom Fusing Book 1 or in the archives of WGBB) and soak 100ºF below slump temp. I would soak for 2 hours and take 2 hours to go the next 100º. My schedule is very conservative.