Large Scale Enameling

Another student from the Glasgow School of Art came to see if I could help with the enamelling of large copper pipe for her MFA show.  Mimi shows the wide appeal of the GSA as she is French Canadian - although I thought her a French national for several weeks.

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.

Knitted Metals and Glass

It is much easier to find things using the internet than it used to be, but I am still surprised at what students can find and work with.  Kathy came from the Glasgow School of Art to ask about experimenting with the addition of knitted materials to glass to form a combined unit.

So the task was to find a knitted material that would incorporate with the glass and that would withstand the heat required to form the glass around the knitted fabric.  The range of threads she was able to source amazed me.  She found kevlar (of course), combined silk and steel, twisted steel threads, monofilament steel threads, copper, and she experimented with knitting a number of other threads.  Of course I was amazed simply at the possibility of knitting metals.

The initial part of the experimentation was to test how the fabrics survived the firings.  The fired results had to be strong enough to support the weight of the glass and be able to be put on the knitting machine to continue knitting the glass into the whole fabric.  Kathy tested kevlar, copper, and various forms of steel in both electric and gas kilns.

 The test with copper within the whole glass, left a large unsightly bubble in the centre and the network of the knitted fabric would be too distracting in the finished piece anyway (The dark marks as the left come from another process).

The test with ordinary steel and kevlar produced unsatisfactory results, as the kevlar (bottom) completely fired away.  The steel was blackened and pretty unsightly (the finer knitting at the top is a carrier fabric to enable re-attahing the fabric to the knitting machine.

Some metals appeared to work better than others.  The twisted steel thread at the top seems to be good, but the small gap shows that it is relatively fragile.  The middle piece shows that a method had to be determined to hold the fabric straight and even in the kiln.  The bottom piece (copper) appeared to be satisfactory until touched, when it just crumbled as you can see where a finger touched the fabric.

A combination of silk and steel (top) seemed to have reasonable results, even though the threads were very fine.  However, testing with the knitting showed it did not have enough strength to be knitted onto.  The coper at the bottom did not bubble this time, as care was taken, but as you can see at the left, it simply broke up at the touch.

The other variation that was chosen was to use the gas kiln.  It fires faster, reducing the oxidisation time for the metal and it also has a slightly reduction atmosphere as opposed to the oxidising atmosphere of electric kilns.  This proved to be the best kiln to work with, although it limited the size of the pieces considerably.

Kathy's next set of experiments was to try to obtain the colours wanted for the replication of the microscopic images of various minerals, which has been her starting point.  Here the contrast between the colours available in threads and that available in glass became apparent. 

  Tests of various combinations of colours were not as subtle as can be obtained from dyeing of threads.

So to increase the colour range and subtlety, powders were applied and manipulated.  Above are some of the tests.

Of course testing these with the incorporation of the fabrics was necessary.  The beginning of tests of combining glass pieces to be able to shape them before knitting them into the whole fabric can be seen in the lower left.


Of course, my involvement was only a small part of the whole of Kathy's degree show.  This was held in the Skypark campus of the School of Art, with each person given a standard space.  From this you can see the wide range of fabrics she developed from her investigation of the microscopic level of a few minerals.  On the left panel you can see the incorporation of screen printed versions of the mineral slices that were her source material.  The colours continue into her other fabrics on the right panel.

As there was so much to do and the technicalities of getting the shapes to work with the fabric were time consuming, Kathy had to concentrate on getting the fabrics correct.  Some of the glass she developed is shown on the light box at the bottom.  She also has several boxes of material showing the development of the fabric-connected glass.

I am happy to report that Kathy received a first class honours degree with distinction.  She also won the Incorporation of Bonnet Makers Prize (one of the Glasgow guilds descended from medieval times and still active).