This year’s group of Girl Scouts met me at Architectural GlassArts again for our fused glass collaborations. Girls age 8-16 years old participated, with most of the girls being in the 10-12 year old range.
After talking safety (how to cut glass, how to handle glass, wearing safety goggles while cutting), we discussed different ideas for themes of the plates. The girls divided into groups based on which mold they liked (and, of course, who their friends were), then began talking about the theme and colors they would be using. They dug through my scraps of glass to find pieces to cover the clear glass blanks that were cut to the size of the mold.
I didn’t give them any rules for constructing the plates, knowing that I may have to tweak the firing schedules a little. But, thankfully, three of the groups did two (glass) layer plates, which are easy-peasy to fire in the kiln.
And, as I had access to Architectural GlassArts big coffin kiln, I was able to fire all of the projects in one firing (except for “A Billion Sunsets” – read on). The “Big Kiln” measures approximately 30″ x 48″ and is able to accommodate a LOT of glass!
After the girls finished working on their collaborative pieces, they started making pendants & sun catchers that they get to keep. The collaborative pieces will be auctioned off on April 29, 2012 at the Lied Center for Performing Arts in Lincoln, Nebraska. (For tickets, contact Jenny Cardwell at 402.875.4345 or by email firstname.lastname@example.org.)
Most of the pieces were fired to 1440º F, which in my home kiln is a tack fuse, but in the “Big Kiln” is a full fuse. So the textures in the plates was a bit softer than I was going for, but not a big deal.
And then… I knew I was going to have issues when firing “A Billion Sunsets.” This piece was piled high with glass that was 3/8″ thick in some spots, but 1/2″ thick in others.
I wanted to full fuse the piece so that it had no more texture, but tons of depth! When you full fuse glass (to 1480º-1500º Fahrenheit), it spreads to become 1/4″ thick. That means that “A Billion Sunsets” would have spread out across the shelf to be bigger than our mold. The solution to that problem is to dam the glass in the shape that you want it. However…
I forgot to put ThinFire (special paper that doesn’t totally burn up in the kiln) down on the shelf, which means that air got trapped under the base piece of glass we built on. When the outer edges of the glass sealed shut against the kiln shelf, there was nowhere for that air to go but up and through the layers of glass above it. (Remember that air expands as it gets hotter, so that bubble may have started out really small, but as the kiln got hotter, so did the little bubble!) So, “A Billion Sunsets” will now have a brilliant sun where I fill in with some sparkly dichroic and some more glass…
Sometimes when you fuse glass together, you aren’t able to clean it thoroughly…this can lead to “devitrification.” Devit is a scummy, dirty looking fog that doesn’t clean off of the glass. There are a few things you can do to fix it. Here is how I’m fixing it: Sandblasting.
Notice the lovely mask and ear protection I’ve got going on. The mask is to prevent any silica carbide (the blasting media) from entering my lungs. Silica carbide is a black, shiny sand that eats away the surface of the glass.
After sandblasting the glass, it needs more attention. Now, it’s got a matte appearance that also absorbs fingerprints. So, next the pieces will go in the kiln for a “fire polish” and “slump.” A fire polish will turn the matte finish back to a shiny surface. The slump gives the flat piece of glass a 3-dimensional shape, turning our glass into functional plates.