Tuesday, July 2, 2013

Yet Another Learning Experience: Using Copper Foil In Fused Glass

After fusing but before slumping.

It's hot here in Oregon, so it seemed like the thing to do was to work with some hot colors! I also wanted to play with some copper foil we bought on one of our first trips to Bullseye Glass.

I used a paper punch to make little flower cut-outs from the copper foil, first sandwiching the foil within two pieces of scrap paper. (And hey, that scrap paper didn't go to waste either -- Ellie claimed the paper flowers for an art project!)

I then chose Bullseye Compatible glass that contains sulphur in hopes of getting a chemical reaction. And I think I did!

The copper foil turned dark, almost black, but in places turned a metallic light blue, that looks super cool. I have plans to try using snowflake-shaped copper foil next time!

So that's what went right. What went wrong, you ask? Two things:

First, I had a couple half-flowers that had been punched with the foil not quite where I thought it was in its paper sandwich. No problem, I thought! I'll just put them on the edges and it'll look like they were done intentionally!

Good idea, right?

Well, the one I put on the edge of red and orange looks great. It's the one I put on the outer edge that's the problem. I apparently left it sticking out slightly when I put the clear glass on top of it. It's also possible that when the glass fused, the top layer of clear glass moved the flower slightly. Sigh. However it happened, it's not only unsightly, but it left a sharp edge.

This close up actually shows BOTH flaws! Can you spot them both?

The second flaw is that I apparently failed to get the foil flowers fully pressed down or something. They were tricky since the petals curled a bit, and I was worried that they would tear if I handled them too much.

But see that ginormous bubble on the left-most flower in the above photo? I'm sure I should consider myself lucky that it didn't burst and leave a major crater, but ... and now that I look at the photo, I see several more big-ish bubbles.

When working with layers of glass, you're always going to have some bubbles. There's just no way around it. But there's a difference between the normal little bubbles and these.

So what do I need to do differently next time?

I'll keep my foil shapes farther from the outer edges. And I'll use GlassTac to glue down my shapes and try using a wooden skewer to burnish them a little to make sure they're not trapping air bubbles.

In the meantime, I plan to visit Bullseye and ask if there's any way to fix the edge where the foil pokes out on this piece. If so, I'll slump it. If not, I'm pondering slicing the piece up and using the smaller pieces as accents in future work.

Got any other tips for me to help me avoid these problems in the future? Leave me a comment here on the blog or on our Facebook page. Thanks!


  1. elevating a couple of the corners with a small piece of clear scrap would allow the foil to off gas and help prevent bubbles, we also use a long soak at 1200 degrees (96coe) to allow for a slow slump of the top sheet of glass which has helped to diminish bubbles.

    1. Thanks for the tip! I'll definitely try that next time around!