Stained glass: Session five

Session five was focused on cutting glass. I had to make sure that I had all my pieces cut and ready for session six as this was when the painting sessions would begin. 

I had already made some headway in cutting out the sections needed, and the only parts left to cut for the main image were slightly larger pieces of green and blue glass. This meant sorting through all the offcuts, out of which I managed to cut another five sections, and then I had to use glass from the workshop's stock, in order to finish the central section. 

Each piece of newly cut glass was put into its place on the cartoon and reattached by tape to its paper template. As each section was completed its number was ringed in red on the cartoon. 

I couldn't find a big enough piece of glass for shape 16, so I decided to re-draw the cartoon and make that section out of two pieces. 

Section 16 is now labelled 16 and 16B

In order to transfer the drawing onto the glass, I used the original template for three sides and a tracing from the cartoon for the side now making the join between the two. Finally once the glass sections were cut, I traced the new cut line from the cartoon onto the paper template and cut that out using the paper cutting sheers that take out a thin strip of paper to compensate for the leading. It might seem very pedantic all this attaching paper templates, numbering etc. but with so many pieces to put together for the final image, it is so easy to get lost. Also cut glass sections tend to look very similar, but they have to fit in exactly the right places, or the jig-saw of the window will never fit together properly. 

Earlier sections already cut are marked by red circles

Once all the central sections were cut, it was time to look at the border. I had some pink glass left over and as this was very expensive, decided to use this as part of the border. (It was also an aesthetic decision, as it brought colour from the centre out into the edges). I was then shown how to make sure all border sections were going to be the same width. 

Making sure the border is cut at a right angle. 

By using the first cut strip as a marker, you can align the wheel of the cutting tool up alongside the edge of the right angle, so that it is exactly positioned for a width that will be the same as the strip above. I managed at this point to break a couple of strips, because the pink glass is very thick and uneven. But I cut enough to get out what I needed. 

As pieces were cut they were placed on the cartoon. 

Section 72 was a continuation of the arm (82) and so broke the symmetry of the border 

The border would be too predictable if it was the same all the way round, and so by responding to the visual arc made by the arm coming in from the side, I could both give the border that needed shift to enliven the dynamics and at the same time anchor the arm idea into the edge of the design. I hope it works, but I shall have to see. A bit of a risk, but without risk you cant learn. 

The purple glass

Jo-Ann also had shown me some purple glass she had available. I had used some for the areas filling in around the leg and Sooty, so decided a little could also go into the border. I realised could use it to emphasise the slight off symmetry caused by my introducing section 72 into the design. I have yet to see it all together on the light-box, but I only have 4 border pieces to cut next week, (blues to sit between greens and pinks) and then I can check how it will all look. 

The state of the border at the end of the session. 

Homework for this week was to make studies for the painted sections, because the next few sessions focus on painting glass techniques. 

See also:

Session one

Session two

Session three

Session four

Session six

Stained glass: Session four

 Most of session four was devoted to cutting glass but an important decision had to be taken at the beginning of the session related to the fused glass section which had been fired during the week. The fused frit circular element, that I had made to represent heel pain was now finished and it posed a few issues. The first was that although it was the right thickness it was lumpy. I could have it re-fired but I decided I liked the look of it and would like to keep it as is. This will make it hard to clean when working on fitting and holding the leaded sections together later on, but I think it will be worth it. The other issue was that I made the circular shape larger than I needed it in relation to the original design, so that I could cut it down afterwards. Now that I have decided to keep the lumpiness, it is impossible to cut, so that It was decided to grind down the edges, and to smooth out the curve, but to maintain the more organic edge, as opposed to the original shape which was drawn using a compass. 

Fused glass made of various course and fine frits

You can just about see the sharp bits on the edge and the fact that sometimes the edge dips inwards, I needed to remove both sharp edges and smooth out the indentations.  

All-Star Glass Grinder

The workshop has an All-Star glass grinder, the main thing to beware of is forgetting to use goggles or to have glasses on to protect your eyes. A smooth movement is needed to keep the curves smooth. (Nb the company that makes these is no more, so replacement grinder heads will be very hard to find)

 

Once the edges had been smoothed off the new shape is placed over the cartoon 

Once in place the Black Sharpie drawn lines indicating the edges between sections of glass, are extended using a white Sharpie onto the fused frit glass circle. An arrow is also drawn so that it is easy to find the top edge. A new more organic circle shape is now drawn using the edge of the glass circle as a template. 

The new shape is drawn and the old one slightly greyed out using the white pen

The new shape cuts into the sections surrounding it, so the first thing I have to do is trace this onto the pieces of pink glass I have already cut. Then I go back into glass cutting mode, first of all recutting the pink and then using the adjusted cartoon, alongside the template sheet that I still continue to cut out, to draw up as many pieces of glass as I can, searching through the trays of glass off-cuts for pieces that are slightly bigger than the paper templates. 

Marked up glass pieces with their paper templates

Once cut I was able to place the sections on the light-box to check how the colour was working. 

Cut pieces set out on the light-box

The 'fit' between sections of cut glass can now also be checked. In this case they seemed to fit pretty well, close enough to not need any immediate grinding off, but when we come to the reality of fitting it all together with the leading, some adjustments will inevitably need to be made. I am personally reassured that I am getting better at the glass cutting and am making less mistakes. In particular I am getting better at controlling the weight of the cutter when making changes in the curve direction when scoring. 

The rest of the session was me cutting glass, including the amber range of glass for the Sooty figure and more small sections of green and blue. By the end of the session I had only 10 pieces of the main design left to cut, but these are larger and I might have to buy in glass for these. Then finally we will look at cutting out glass for the border. 

See also:

Session one 

Session two

Session three

Session five

Stained glass session 3

Using paper templates to choose which off-cuts I could cut out from 

This session was mainly focused on glass cutting. I had had delivered to the glass workshop a sheet of  'Lamberts Gold Pink on Clear' glass. This was going to be the base colour for the leg and arm sections of my design and as it was hand made and very expensive, I needed to do the cutting very carefully. Because of this, before I started, I cut two sections out of much cheaper off-cuts in order to practice the techniques learnt last week. 

During the previous week I had bought my own leading sheers, so was able to cut the paper templates with my own sheers. I was now getting very used to the small repeated scissor action when cutting curves. As before these templates were used to mark up the glass for cutting. However when it came to using the pink glass, the most important issue was deciding which side of the glass to mark up and score. 

Lamberts Gold Pink on Clear is a 'flashed glass'. When scoring flashed glass you need do this on the unflashed side. If you score on the flashed side, the wheel may only penetrate the thin flashed surface leaving the thicker base glass unscored and this can cause the glass to break unpredictably. So my first job was to find which side was which. I found this very hard, as it was not easy to spot the difference.

Flashed glass is a type of specially produced mouth-blown sheet glass. Colouration is created by means of the flash technique, hence the name. The clear or tinted carrier glass is over-laid with one or two layers of coloured glass. 

Once cut you can see the thin coloured glass layer by looking at the side as in the illustration above. However my new glass sheet had 'soft' edges due to its manufacturing process, which also means that it can be thicker towards the edge where it finishes, so you also need to avoid this when marking up. 

The sheet of pink glass had been cut from a larger sheet, so had a sharp edge

My sheet had a label stuck to the flashed side, but I wasn't sure whether this was just chance and I had to look carefully for 'clear spots' in order to decide. I needed to keep checking with Jo-Ann which side was which and didn't yet feel confident. More experience with various different sheets of glass will I'm sure help, at the moment the fact that flat glass sheets are made in different ways is just part of the learning curve. 

I marked up the glass first of all by dividing it, into a strip that could then be used to cut out my shapes. This seems like a way of wasting glass, but I was assured that in this way, each section is easier to handle and therefore you get less breaks and any mistakes cant damage the whole sheet. 

Two paper templates were placed on the full sheet and it was marked for cutting and then cut

Paper templates are now drawn around and are then scored and cut out

When scoring deep curves, which some of my shapes had, I needed to do this as a series of shallow curves.  Otherwise, the glass might break off in its own direction.  A later use of a grinder will finish these off, but they need to be as precise as possible. 

Because I was new to the cutting process, I was still getting the weight right and I did tend to put too much weight on my cutter, something that Jo-Ann could pick up by listening to how loud the scoring sound was. The more I cut the more I was able to control this. Much of the learning resides in your body muscles and you cant quite describe it in words. How you hold the glass cutter, how one hand guides the other, how you twist your body to ensure the cutter follows a smooth curve, how you need to lower your body, so that your eye level coincides with the action of the scoring, and how you keep focused on the drawn line as the cutter wheel moves along it, are all essential things to do and they are seamlessly integrated in the doing. It was also important to remember between each scoring to use the dustpan and brush to remove any traces of glass splintering from the cutting surface. 

At the end of a day's cutting I had 15 sections and I need just over 80

Although working slowly I managed to get all the pink glass pieces cut out and I was able to check on how they were beginning to visually work, by placing them on the lightbox. Finally I lightly taped each cut section to its paper template, so that it was easy for me to check its number and position in relation to the cartoon and then on the cartoon circled in red all the numbers of the pieces that had been cut so far. 

During the process of cutting the pink I had made one bad mistake and this was when cutting the piece for the arm, which I had tried to do in one. The glass was broken in the wrong place, (I could now see clearly why I needed to do the scoring using smaller sections rather than trying to cut out everything from the whole sheet), I had tried to break my glass along a curved scored line by using pliers that were not placed close enough to the score. Jo-Ann pointed out that perhaps the piece was too big anyway and that I could make it in two separate sections. I had to go back to the cartoon, adjust it and number the additional piece. Then cut out a new template and find a pink off-cut out of which to cut the new addition. A useful experience as I realised that what seems like a fixed thing once the cartoon is drawn up, can still be adjusted in response to what happens. 

Course frits, fine frits and powdered frits

I then turned my attention to the fused glass section. During the week this had been fired and it had several holes in it which would make it very difficult to cut, so I needed to fill these and sort out the edges which were splayed out blobby shapes. I used various frits; course and fine as well as power to do this. As I filled the holes I was hopefully able to keep the design working. Finally I used clear frit to hold it together. The big issue here was thickness. I had to make sure it was not too thick or too thin, as this fused glass section has to fit into the same leading as all the other types of glass used. Finally I used fine frit to cover the 'mess' around the edge, so that on firing it should be less blobby. Nb before starting making these additions I placed the fused frit circle over my cartoon to check it was about 1cm bigger all round than the shape I was finally going to need. 

Fused frit circle with additional mixed frit and a layer of clear frit to make sure all holes are filled

This work was done on a kiln shelf and then other pieces were added from other people, so that there was no wasted space in the kiln. (I.e. to not just do what you want to do in the middle of a shelf, leave room for others)

Finally all my pink offcuts were put in the bottom of a plastic container, the remaining pink sheet was put away in a safe spot in the glass rack and I covered the offcuts with cardboard, so that all my cut pieces could be laid flat and one slightly longer piece that I thought was more fragile, was individually wrapped in cardboard and this container was put away for next week. 

Offcuts and cut pieces collected together in a plastic container.

See also:

Session 1

Session 2

Session 4

Session 5

Stained glass and film

Stained glass: Session 2

The second session began with a checking through of the cartoon I had made during the week. 

Stained glass cartoon: Sharpie on paper just over A1 size

This was seen as OK, just a slight adjustment was needed near the top edge where the leg meets the border, it required a little straightening to ensure the line met the border more at right angles. The next job was to trace this with a Sharpie, onto another sheet of white cartridge paper, cut from a roll, (approx. 90 gsm) and using a large lightbox in order to see the cartoon below. All the areas of both drawings that corresponded to pieces of glass that would have to be cut, were then numbered, so that it was easy to see where each piece was to go, by having one uncut template to always refer to. The set of shapes that are being cut out are made to draw around and by having a number on one side you always know which way up the paper needs to be. Everything has a purpose. I began to realise why the paper for the cartoon needed to be the weight it is. Too thick and you cant trace through it on the light-box; too thin and it becomes impossible to trace around. The Sharpie creates a very clear line, it is therefore easy to trace. However it is also its ability to be used to draw smooth curves that makes it a vital tool, it can ride over the paper easily and it does not snag as you change curve direction, or thicken and thin as a more italic drawing tool would. Of course a Sharpie is also designed to draw on glass as well as paper. The chosen Sharpie is a 'fine' one because its thickness is roughly the same as the thickness of the heart of a standard H section lead came.

The H section of lead came

Numbered cartoon and tracing (Nb the tracing has now been cut out along the border edge)

Once numbered in exactly the same way as the cartoon, the tracing was then cut out as a rectangle up to the edges of the glass cutting border, using normal good quality long bladed scissors. The traced cartoon edges are now as you can see from the image above, its borders. The next stage was to begin the process of cutting out the individual pieces of paper which will be used as templates that allow the transfer of the shapes to the pieces of glass that need cutting. However to do this special scissors are needed, alongside a very particular cutting action. 'Pattern shears' are used that cut away a strip of paper that is the same thickness as a lead came section. 

By cutting along the Sharpie lines with the pattern shears, you remove approximately 2mm, the gap required for the insertion of a standard H section lead came between glass sections.  However you need to make cuts using lots of quick small movements, if you want to cut a curve, which are a very different set of movements to those normally used when cutting with scissors. (I had to practice curve cutting first on a spare sheet of paper). Once you get the hang of it you can cut out the first few shapes. In my case we chose shapes of some blue and green pieces of glass that could be made from some off-cuts, so that I could practice glass cutting on pieces that were not too expensive. Once the paper templates were cut out I was then shown how to use these as stencils for marking out the glass pieces I needed (using a black Sharpie on clear glass, and a white one on dark glass), each time looking for useful existing design elements, such as a straight edge. If an off-cut had a straight edge this became a useful starting point for transferring the shape, as I could put straight edge to straight edge and save myself one line of cutting. Once traced out onto the glass pieces I began to start learning the processes associated with cutting glass.  

The pattern sheers

The thin strip of paper that the pattern shears leave behind

Before being allowed to use the actual pieces I had to practice on spare off-cuts. There were a few key lessons. The most important was getting my body into place so that I could see the glass cutter's cutting wheel really clearly. (Nb. during the previous week I had bought my own glass cutter and a can of sewing machine oil, which I used to fill the interior of the cutter, so that it was properly lubricated). By splaying my legs open wide I could get my eye level down to see the wheel as it scored the glass. By listening to the sound of the crackle that emerged as I moved the glass cutter along, I could check if I was holding it down with enough pressure. I was using my right hand for holding the glass cutter and pressing down, and left hand for guiding it along the line. After a few goes on scrap pieces of clear glass I was judged to be good enough to cut my 4 green and blue glass pieces, and I then cut them out without mistakes and they were put away for the next session. 

About to practice cutting a short curve using an off-cut of plain glass (note the way round the cutter is)

Holding glass ready to break it

There are a few more things to remember. Don’t start at the edge: Begin a score roughly 1/16 inch in from the edge, however you complete the score by rolling over the end edge. Try to achieve a smooth even consistent pressure all along the score, as well as trying to achieve a steady speed across the whole length of the line. (In one case when trying to score glass with a rougher surface I came to a halt, because I hit some sort of glass bump. I managed to then continue by putting the glass cutter back in exactly the same spot and carrying on. The glass broke along the line as it should have, but I had to use two pairs of pliers to hold it, rather than use the hand grip) You normally break the glass by holding it thumb on top and folded fingers below. (see image above) Hold arms out straight and downwards and once you are sure your bent fingers are close to the score but not straight underneath it, simply twist your wrists outwards. However through trial and error I found that when hard to break after scoring, you might need to hold with pliers and if so, best to start twisting a plier close to the edge where you finished the cut. I also sometimes found it useful to put the scored glass next to the table edge, then using the table as support, broke off the waste glass using glass pliers to hold it. 

I was also beginning to have to think about the fused glass areas. The most important being the 'pain' area around the heel. 

Detail of painted image that is being translated into stained glass

Detail of cartoon

In the cartoon this area had had to become clarified, but the painting pointed to a much more organic series of forms which had been evolved in relation to my earlier work on interoception and the representation of pain. So it was decided to use this area of the work to investigate fusing techniques. I therefore, using a found bowl of the right size, used it to draw out a circle on a glass kiln shelf that was approximately one centimetre in diameter wider than the circular area indicated in the cartoon. I then used a variety of coarse frits to build a form that was to be fired and that would by the nature of the way glass flows when heated have holes in it, that could be likened to some of the visual properties in the painting. Hopefully this will be fired during the week and responded to during the next session. 

 

Various course frits contained in a circle ready to be fired.

As always there were other things to consider. A good way to control the amount of frit used is to put some in the lid of the accompanying frit container. As you drop the frit, from the lid in order to achieve an open random feel to its distribution, there is a way of holding a frit container lid and moving it in a backward and forward rocking motion, alongside using a spare finger to tap the side of the lid, that helps give a better less 'clumped' distribution. 

Once you feel you have enough frit on the kiln shelf, the final issue is how to deal with all the frit that will have spilled out from your design. Using a fan shaped brush this was carefully collected and pushed towards the edges of the shape. However I had to be careful not to push these bits of frit into the circular mass, as this would build a 'wall' around the edge, and so I was careful to get these random frit pieces to touch but not to overlap too much, in this way I hoped to avoid an unsightly raised edge. 

Materials needed for session two

Large sheet of 90 gsm cartridge paper to make a tracing from the cartoon that will act as the main template. This was cut from a roll supplied by HSG.

Black Sharpie: £2.00

White Sharpie: £10.98

Good quality long bladed scissors to cut out the copied cartoon. Cost: £4.99

Lead Pattern shears Creative Glass Guild Cost: Cost: £8.50

Glass cutter: Oil Glass Cutter Silberschnitt 3000  Cost: £37.86 (including shipping and VAT)

Lubricating Oil for the glass cutter Cost: £8.39

Coloured glass: The glass cost depends on colour and type. In this case the pink I needed was obtained from Pearson's glass. One sheet 610 x 455mm of 'Lamberts Gold Pink on Clear' cost: £226.99

Frit and some cheaper glass types and colours were provided by Hannah Stained Glass. (HSG)

See also:

Session one

Session three

Session four

Session five

Soldering

Stained glass artists