Of course, with everything moving so quickly, we didn’t have time to make extended vacation plans. It’s only three weeks anyway before I start my new job, so it wasn’t worth it to go somewhere far away. But my sister, who lives near Copenhagen, had invited us over — and we hadn’t been there in years, so it would be fun to stay with them again. They now also have a vacation home, and the shed there has been converted into a glass art studio. After a few days in Copenhagen, we moved to the vacation home and my sister visited a few times to help us make a glass project!

I have been really interested in the glass ‘dots’: drops of glass that you stick to a transparent piece of glass. It’s what I used for the Estus flask. But instead of firing it very hot for a ‘full fuse’, where the dots melt completely and you get left with smooth glass, I wanted a cooler firing so that the dots remained domed. My sister gave me a circle of transparent glass: a reject from a commission she’s working on right now, but perfect for my purpose.
I did not have a pre-set plan and just went where the size and colours of the dots took me.

This was the result of an afternoon fiddling with tweezers and glue. The dots are glued with normal hobby glue — that will burn off in the oven, but at least prevents things from shifting around before then. I may have used too much glue in places, but it did not cause problems.

Of course, if the dots would not melt fully, then there would be space in between them. With stained glass windows in mind, I asked my sister what to do, and she suggested using black glass powder. With a small brush, I brushed that in between the dots. Because it is much finer (really glass dust), it would melt at much lower temperatures. I had to wear an industrial mask — you don’t want to breathe in glass particles. Trust me on that.

It takes about 24 hours for a firing to be complete, as the glass has to stay at certain temperatures for a certain times for proper annealing. And then it has to cool off slowly, otherwise the stresses in the material can cause the glass to shatter. And since the oven uses electricity (and a fair amount of it), it pays to wait until midnight to start heating up the oven — the computer has a ‘waiting stage’ in its program.
That evening, we had arrange to meet up with some of my former colleagues with whom I still play RPGs, and we were back very, very late. So the oven had cooled off enough to open! We were too tired to do anything else than to take out the fire-proof tray with our projects, put in another tray that had been prepared, and turn on the oven. I took a quick snap of my project as it came straight out of the oven.

This is the next morning. The dots act as tiny lenses and refract the light. I do think the black glass in between adds something important. It’s not as nicely spread as I would have wanted. I might have brushed too rigorously because I did not want to run the risk of some specks of black dust getting stuck on the dots themselves and diminish the luster.

You can see how in some places, the black glass did stick to the underside of the dots. But it all has melted while the dots retained their shape.

On this side view, you can see clearly how the dots remained ‘dot-shaped’.

It also works against a darker background. That really brings out the different colours.

This is what it looks like from the ‘back’ of the project. That has a whole different feel to it and shows the ‘stained glass’ effect a bit better.

The dots act as tiny lenses. Here I held it against the carpet in the ‘sun room’, and you can see it reflected/refracted in the dots.

My project used up a lot of dots, and my sister is working on a huge commission that also requires quite a few dots. So I felt a bit responsible and decided to help make more dots.
The cool thing about glass is that when it completely melts (at around 815 Celcius), the surface tension makes it want to become 6 millimeters thick. It will form drops of that thickness, and when it cools off again, those drops harden — that’s what the ‘dots’ are! And with glass being so hard, it is almost impossible to cut round shapes in it: you basically approximate a curve by chipping away smaller, straight pieces. Which means that if you need a lot of different-shaped pieces, you get left with lots of very small pieces.
So the trick of making dots is to collect those pieces and fire them at a high temperature. It takes a hot firing in the oven (and thus quite a bit of time) but it is a great way to recycle what would otherwise be waste material.

The plates that go into the oven are hard ceramic plates, sometimes with a ‘slurry’ on it as a releasing agent. You want to keep some space in between the pieces, so that they don’t melt together.

It is a nice little job to simply take the pieces that are available and arrange them. Very satisfying to see the area get filled up, and to find the best-fitting piece for a particular spot.

This is how the plate goes into the oven. The heating element is embedded in the (heavily isolated) lid. The little black bit on the right on the inside is the temperature sensor, and the box on the right of the oven is the firing computer. Close the lid, create the program, and then just wait until it’s all cooled off enough. With the heavy insulation, even cooling off takes a long, long time!

And this is what greeted us when we opened the oven! Some of the pieces turned out to be too close together so they melted together, making a multi-coloured dot. Some dots got weird shapes because of that too, but that is maybe also a charming effect.
Have some dot glamour shots! I put them all in a plastic, lidded container, so they can be poured out and sorted when needed.




Crossposted from my blog. Comment here or
at the original post.