This required a lot of experimentation. The electric kilns oxidised very badly if placed in a cold kiln and taken up to temperature. The glass kiln worked much better with this kind of heating. However, it is known that copper enamelling is done by placing the copper in the annealing oven when it is hot for a few minutes.
Among the first experiments were getting the enamel powder around the whole of the pipe. Normally, enamelling is done on a flat surface, and the powder needs to only sit on top of the copper. With a three dimensional surface, a flux needed to be applied, which would be viscous enough to stay on the pipe without dripping and also hold the powdered enamels.
So be began experimenting with temperatures required. It became apparent that there was so much heat lost in opening a large kiln that we needed to heat the kiln 50 to 100 degrees above the 800 target temperature. This depended on the size of the kiln, but not in the way expected. The smaller kiln lost more heat and required more time to recover than the large kiln. So the large kiln needed only about 50C over the target temperature, and it recovered to 800C within 5 minutes which was enough to heat the pipe and fuse the enamel to it.
This heating process was very dramatic as you can see from the photos of the process:
|Getting ready to open the kiln|
|Placing the pipe in the kiln|
Even though I was standing 4 metres away, I could feel the heat almost instantly. But denim jackets put on backwards, gloves, heat reflecting sleeves and face guards were sufficient for the brief exposure to the intense heat.
Then once the kiln climbed back to temperature, they had to reach in and take the cured pipe out without letting it touch the floor of the kiln, or burning the surface on which the pipes were cooled.
|One of the larger diameter (50mm) pipes after initial enamelling of the base colour.|
The enamelled pipes were of course only part of Mimi's MFA exhibition. All the MFA students exhibit in an old glue factory! The most interesting part of the building for me was the tanks which were still in the building. Other wise it was a series of rooms and large (probably) drying areas.
|One of the pieces at the entrance to a room|
|Another free standing piece|
|One of the longer, but smaller diameter pieces fixed to the wall|
The whole MFA show was varied - from a number of video pieces and installations, installation pieces some of which had a craft appearance, photography, but surprisingly (to me, but not others who follow the conceptual art movement) very little painting.
It is good to report that Mimi received her degree and is now off to mount an exhibition in Germany, before getting ready for others in the UK.