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).

Alexander (Greek) Thomson House

One of the great things about this job is that you get to see houses that might go un-noticed because of their out-of-the way nature of their location, or non-descript face.

Such was a house I was called to to look at storm damage to the stair window.  As I finally negotiated my way down a lane and missing the entry causing me to go on to a railway station that I did not know existed, I finally went across the cattle grid to be presented with this.

Yes, as I was to learn, this is a Greek Thomson house, possibly his first outside Glasgow.  This is an architect of such importance that there is a society established to study his works.  This grand house is impressive in its size as well as in the amount of light he allowed into the building.  No other architect at the time was filling the wall with so many windows.

The front door is as impressive as the rest of the house.  And probably the scale was meant to impress visitors with the wealth of the owner.  The front doors are twice the height of the average person.

The back of the house is no less impressive than the front.  The house is marred by the modern extension at the left, but still is a handsome house.  Note the number of windows all of which face over the River Clyde to the south.

This gives an impression of part of the view just from the garden.

The view from the first floor must allow views over to the Mull of Kintyre and the Isle of Aran.

But now I have to get to work.  This is the external view of the area of storm damage.

Fortunately the leaded glass had been covered with protective glazing some years ago.  This meant that the falling slates and guttering extensively damaged the external glazing, but not much of the leaded glass.

As I was welcomed into the house, I noted the generous cloak rooms with the fine cornices at the upper level of the walls.

This kind of elegant decoration continues into the modern down stairs lounge -  which would have been the dining room originally.

As we went round the stairs to the kitchen, there were a pair of windows under the stair:

And just to the left of them the door into the kitchen:

You can see from these pictures that coloured glass was not an important element in Thomson's architectural decoration.  What there is is simple and elegant, relying on varied textures in the glass for interest.


Now, really, I must get to work.  The falling roofing materials had broken the protective glazing extensively, and in some places had come through to the leaded glass.

My job was to get up to these breaks, which were about 4 metres above the landing, and repair them.  Fortunately, the client has a friend who runs a scaffolding firm.  The scaffolding was put in place for me to get up to the glass.  It was difficult as much of the broken glass was pieces next to each other and the lead had been  twisted by the impact.  The obvious pieces are at the right centre of the picture, but there were others broken under the glazing bars.

Fortunately the broken original glass has modern imitators that are a very good match, so I was able to fit the glass and leave it appearing to be original.


I have been to this town many times, but would never have seen the outside of the house, let alone its inside.  The owner of the house is proud of it and happily pointed out lots of things to me, but of course does not want a string of visitors.  So, my job is a good job for someone - like me - who is interested in domestic architecture

Brilliant Cut Glass

While being at the house in Bathgate doing the removal and installation of the cloakroom window, I could not help but notice the glass in the front door.

This is the first brilliant cut glass that I have seen (not that there are not others, of course) in a domestic front door.  Upon enquiry, it turns out that this building of three flats was built in the early 1920's by a local foundry owner.  It may be that the wealth available lead to the commissioning of this front door.

It is not only etched with hydrofluoric acid but also white acid (a combination of alkaline and acidic chemicals to give a more pale etched colour).  The white acid effect can be seen in the thin line surrounding the clear brilliant cut lines.

You can also see the effect of the white acid in the paler upper central area of the panel.  This shows the effects of the two acids clearly.  The chemical combination gets its name from the whiter appearance achieved with its use.  It is rarely used nowadays because of its heat-creating reactions and subsequent risk of explosion.

The brilliant cutting can be seen in the six heart-shaped petals at the top of the stylised acanthus leaves and above the fleur-de-lys emblem at their junction.

This lower section of the central panel shows the effect of the brilliant cutting.  The four "cartouches" shown here have lines at the curve, showing the use of different wheels to do the cutting.  The rectangles and circles are relatively easier to cut than the sweeping curves leading to the circles.

The bottom of the door panel is relatively plain, but contains some superb artistry in the brilliant cutting.

In this emblem at the bottom of the door, the cartouche is cut in one sweep of the wheel.  The inner detail is cut with two sweeps of the wheel for the outward flaring shapes and finally the points put in with a "V" shaped wheel.

The side of the panel shows more of the skill of the cutters. Three linked olive shaped areas are cut and polished beside a group of faint cartouches.  Below is a group of three heart-shaped references to honesty seed pods.  But a simple and difficult feat is the straight lines cut all the way around the panel.

The corner again shows the work in creating both curved and straight lines.  They are all incorporated with the acid etched designs in an almost seamless manner.

My admiration for the skill involved in producing this door panel relates to the requirement that the lines and shapes are cut into the glass and then ground repeatedly with finer an finer grits until polished.  And there were no slips!  Secondly, the whole piece of glass (around 120 cm by 80 cm and 8 mm thick) was suspended and balanced by weights to enable the craftsman to manoeuvre the glass over the spinning wheels.

This work deserves to be at the very least listed as an important piece of work and at best incorporated into a museum setting as this work cannot now be reproduced as all the hand skills have been lost and the computer controlled brilliant cutting machines cannot reproduce the curves of this design.