Just over a year ago, I started making ‘drop vases’. A drop vase is where a flat piece of fused glass is suspended over the kiln on a mould with a hole in it. As the kiln heats up, and the glass becomes softer, it drops through the hole, creating a vase or a deep dish. Pieces made in this way can be stunning but it’s a long process from start to finish and as such, drop vases or bowls tend to be more expensive than slumped pieces.
I’ve decided to do this blog to a) show you a new piece and b) give you some idea as to what is involved so you can appreciate the work which goes into making drops.
To begin with, you have to create the ‘blank’. This is the fused piece of glass, which is flat. The design you make at this stage only gives you some idea of what the end product will be because obviously, things look different when the glass is dropped and gravity takes over. For this piece, I decided to make use of ‘on-edge strip construction’ which is using the edge of the glass rather than the flat surface. Here’s what I created:
Now, a lot of people like neutral colours, and that’s great. But I love colour. When you have such wonderful art glass at your disposal, I just can’t resist using the bright colours. This piece is made up of dark blue and a mix of opal and transparent orange.
The next stage is to fuse the ‘blank’. Here it is in the kiln, ready to be fired. The piece is dammed because it’s thicker than most fused glass, at 9mm instead of 6mm. If this piece was fired un-dammed, it would spread out, distorting the design and making the piece thinner.
When it comes out of the kiln, it looks quite dark but that’s fine, because when gravity takes effect, the colours will brighten. I now need to fire this blank over the mould, in the kiln. I had already made the mould previously, using ceramic fibre board. The piece will be elevated off the kiln floor on posts, as you can see from the set up here:
There is the potential when firing drops, for the whole of the glass blank to fall through the hole in the mould. There are numerous ways of dealing with this but in this instance, I have used scrap glass all around the outside of the piece. These scraps will fuse to the edge of the piece during heating and will then hold the edge of the piece to the mould.
This piece is now fired and overall, including cooling, this takes a massive 30 hours in the kiln. When it reaches the temperature at which it starts to drop (called ‘process temperature’), I then open the kiln in 5-10 minute stages to see how far it is dropping. Bear in mind that the process temperature for this piece is 677 centigrade. To open the kiln at this temperature requires special glasses, an apron to protect my clothes, and thick gloves. This piece was dropped sufficiently after 35 minutes. At this stage, I can forward the kiln programme on to the next stage to stop it from dropping further.
When the piece comes out of the kiln, yet more hard work is needed. As you can see from these pictures, the brim needs to come off. As the brim is very heavy with all that scrap glass, if we were to cut it off right up close to where the piece has dropped, the weight of the brim as it pulls away from the bowl could cause the whole thing to crack. For this reason, there are two processes to remove this brim: cut off the excess with a tile saw, followed by more intricate cutting with a cutting wheel on a dremel. You can see both processes here:
I get Rich to do the cutting because frankly, after all the labour I’ve put into the piece so far, I am just too scared to do it myself! And of course if it goes wrong, I can blame him…..
Unfortunately, I can’t show you any photos of this because Rich wasn’t around when I did it and I couldn’t hold the piece steady on the lap wheel and take a photo. I’m sure you can imagine the process though. Finally, after grinding, I can polish the piece using cerium oxide – this gives the ground edges a high polish finish. And this is the finished piece:
I’m really pleased with how it’s come out, even if there are times during this mammoth process when my heart really is in my mouth as there is so much which could go wrong. I hope you like it and can appreciate what goes in to what looks like a simple little bowl.