A common question from new recycled glass artists is “How do I make glass donuts and rings?” Happily, I’m here to tell you.
Recycled bottle glass donuts are made from the neck of bottles, cut into slices, typically with a tile saw. There are some easy things to remember for donut success:
1. Taller isn’t always better.
Here are two cobalt rings, one about 3/8″ tall, and the other about 1″ tall. Fused in the same batch, using the same firing schedule:
You can see the shorter donut has rounded nicely, the taller one has rounded, but the top has slumped over and inside, making the hole smaller and the inside slightly lumpy. A good optimum height for donuts is 3/8″ to 1/2″ tall.
2. Smooth cuts matter.
Not to say that smooth cuts are better, but you should be aware of what will happen when you fuse donuts that are cut a little differently.
Here is a veritable rainbow of color donuts, all about the same height, all fused with the same firing schedule.
You can see the clear bottles didn’t melt quite as much, and the light blue also didn’t smooth out wonderfully. If one of your colors is giving you problems, try a different bottle of the same color glass, preferably a different brand. Not all bottles are created equally, the issue may be with the glass!
Recycled Bottle Glass Rings
Rings are made by fusing thinly cut slices from the body of a bottle. After a question from a wonderful reader, I decided to do some experimenting to find the optimum slice height and bottle thickness for predictable fused glass rings.
What I found:
1. Most wine bottles are very close to 1/8″ thick measured through the wall of the bottle. To measure, cut the top off of your bottle and measure the glass from the inside of the bottle to the outside.
2. Most champagne bottles are 1/4″ thick measured through the wall of the bottle. This becomes important later.
3. It’s really challenging to cut smooth, regular rings from a bottle, any bottle.
Using several different colors of bottles, I tried to cut comparable height of rings from each bottle. I succeeded, more or less, some are more and some are less. The conclusions are the same however:
These rings are from a sparkling chardonnay, bottled in a champagne style bottle. As you can see, the thinnest fused the most smoothly (it had a crack that I didn’t see in it). The right hand most ring is the sturdiest. Note that even though the thinnest ring is fragile, it is still TWICE as thick as the thinnest wine bottle ring.
My conclusions and recommendations from this series of experiments are:
For best results, use smoothly sawn donuts that measure between 3/8″ and 3/4″ tall
For rings, measure the thickness of the bottle and cut the rings so the height is 1.5x the width.
Use a full fuse firing schedule.