Glass fusion was lots of fun. I would love to get into it a bit (lot) more. Today’s projects are just in the kiln now, so I’ll post photos tomorrow. I have plans for them, and plans for more projects, too, if I could figure out how to fuse them myself (at the store, which rents out the kiln). Kaleidoscope wheels fused? Yes, I think so.
Glass fusion is surprisingly technical (well, surprising if you don’t think about it at all before you start). Since glass — like all materials — expands as it heats up, you need to be careful what glass you put together. For instance, I used Bullseye glass, which has a COE (coefficient of expansion) of 90. Julie who was also taking the class used Spectrum, COE 96, and Dolores brought her own handblown beautiful beautiful glass, COE 98. Within 2 points, you can usually mix glass, so she used a Spectrum 96 base.
The coefficient of expansion is how much the glass expands per degree celsius the temperature is raised. So my glass expands 90×10^-7 — which means that if I had glass that was 10cm long, if I raised the temperature 10 degrees, it would be 10.000009cm long. You need to use glass that heats at the same rate. First of all, you’re raising it to 1000 degrees (celsius) — this will end up making a difference. Glass attached to other glass of a different COE will end up breaking.
You need to warm it up slowly at first, so that you don’t end up with molten edges and a solid centre (or, in other words, a broken piece). You need to cool it down slowly, too, otherwise you’ll end up with crystals forming, and the glass will be opaque and ugly. Fusing takes a long, long time.
And prechecked glass — glass that’s been checked to see that it’s self-compatible, that the colours don’t turn when you cook them — is expensive. Red is the worst, of course (made with gold oxides), so I used it for accents. Still, because we only 3, we had lots of kiln space, so we all could make lots of projects. And one of us worked very small, one only did one thing, and I was the third, so I will have 11 projects (7 small, 4 medium). At least 3 of them (small) are boring, but I learned.
One of the things I like about fusing is that you don’t need to grind down your pieces. depending on what you’re doing, you don’t need to cut them too precisely, either — the edges will melt, anyways. And also you can’t wear stained glass as jewelry, you can wear fused glass as jewelry. I would like to buy some dichroic and make some fused dichroic jewelry . . . I want my own kiln, really. I want to see what hotter or cooler or longer or shorter times & temperatures do . . . I want to make stuff for jewelry and bracelets (bracelets!). I want to make beads. (Lukcily, Julie in the class also does, as does a friend of mine, so we might manage to get a class running.)
There is a class on fusion & slumping. Slumping means making your flat glass unflat, by melting it into molds for bowls or vases or sushi dishes. I want to take this class, too — possibly in July when it’s first offered. How much fun! I’ve always loved those glass bowls. This is another thing I could use a home kiln for. See how useful it would be?