Finger Protection While Grinding

 Grinding lots of glass pieces often leads to a number of small cuts on the tips of your fingers. There are several things that can be done to reduce these cuts and the tenderness that comes from lots of grinding.

Various methods of protection are used.

Altering the fingers used to press the glass to the grinding bit.

Gloves –  It is not recommended that you wear gloves around rotating machinery. There is too much risk of injury, even on a small grinding machine. Some of the alternatives to gloves include plasters (band aids), masking tape, electrical tape.

Finger protection you can buy include rubber finger protectors, finger tip pads, finger caps (as used in counting money).

Other tools are made to hold the glass such as the grinder cookie

and Nick's Grinder's Mate 

Prevention
The sore fingers are usually caused by tiny cuts from the glass. So, all these methods are ways of putting something between the glass edges and your fingers. More importantly, you need to think about your practice if you are getting sore fingers while grinding.

The first thing is just to lightly grind all the way around the piece. This can be quick, and should use minimum pressure. This to is to take the sharp edges off the glass.  You can do a simple, light grind all the way around the piece. This removes the extra sharp edges that often remain after breaking the glass.

You can go a step further and do a light arris around the piece. This is just lightly holding the glass at about 45degrees to the grinding bit and going all the way around on all sides. This does not take off the shape of the piece, but gives a more rounded feel to the piece.

An illustration of the effect of holding the glass at an angle to the grinding head, although it need not be so much.

If you have to press hard to achieve the effect you want, it may be that your grinder bit is badly worn. It may also be that you need to have a coarser bit to achieve the amount of grinding that you need.

You should not be pressing hard in any case. This will wear out bearings on the motor and reduce the life of the bit.  Let the grinder do the work. Many people seem to put huge pressure on the piece to grind away the waste more quickly, but this is actually counter-productive. Less pressure means less fatigue, less chipping at the edges, fewer broken pieces, and most importantly, fewer cuts to the finger tips.

You should use medium pressure to allow the diamonds on the grinding bit to do the work. This will be about the same pressure as scoring the glass.  Fine work requires a fine grit, removing a lot of glass requires a coarse bit, not more pressure.  

If you frequently have to remove large amounts of glass, you need to review the accuracy of your cutting. You should not be relying on the grinder to do more than tidy your cuts.

Remedies
There are several remedies to relieve the soreness:

Cucumber melon
Vitamin E
Tea tree oil
Germolene
Antibacterial hand lotion 

Cementing Leaded Panels

Cementing panels is as old as leaded glass - over 1,000 years - so it is a time-proven process using simple materials. The object of cementing is to make a leaded panel weather and water tight and sturdy. It can be messy and dusty, so putting on an apron and a dust mask are a good idea.

Part 1: Cement

You can make your own lead light cement as the materials are fairly common and safe to use.

Recipe

7 parts whiting/chalk

1 part boiled linseed oil

1 part mineral spirits (turpentine or other)

(All of the above measured by volume)

1-2 Tablespoons lamp black or other colorant – black poster paint, acrylic paint or oil paint

Tools and Materials for Making Cement

The mixer should be capable of mixing bread or similar stiff dough. The existence of a dough hook among the beaters is a good indication.  Also it is best if the bowl is rotated as this makes for much easier and more fully mixed cement.

Method

Add the whiting (reserving about one quarter) to the linseed oil and mineral spirits. Mix this well, by hand or with a domestic mixer capable of mixing bread dough. When these are mixed thoroughly, check the consistency. It should be like molasses on a cold morning - barely fluid.  At this point, add the colourant, so you will know the current colour and can adjust to make it darker.

Add more whiting as required to get the consistency you want. Experiment a little to find what suits you best. If you have to deliver the panel quickly, for example, you need to increase the proportion of mineral spirit. The mineral spirit evaporates relatively quickly, leaving a more rapidly stiff cement.

Being mixed

Note that the cement is nearly finished mixing as the ribbons of material are forming in the above photo.

Mixed and ready for application

When fully mixed the cement should only slowly drip off the mixer beaters.

Comment

You should make only what you will be using on the current project, as the whiting separates from the linseed oil and spirit relatively quickly. The commercial cements have emulsifiers to keep the whiting from settling and so extend the life of the product. Since making your own is cheap and quick to make, there is no saving in making a lot.

Part 2: The Start

Start on the side that is already facing up after soldering. This normally will be the rough side. This way you do not have to move the panel much until it has stiffened with the addition of the cement.

Starting with the rough side enables you to cover all open bubbles, rough glass (waffle, ice, etc.) and all painted glass with masking tape before you start. Put the tape over all the relevant areas of the panel, then use a sharp craft knife to cut the tape at the edges of the came. The cement will go under the came, but not into the texture of the glass. This will make the clean up of the glass much easier after cementing.

Adding the cement to the panel

With the panel on the bench, put a dollop of cement on the glass and rub it in all directions with a stiff, but not hard, bristle brush to force it under the lead. 

Scrubbing the cement under the leads

Adding whiting

When the cement has been pushed under all the cames, but with a slope of cement showing, spread a little fresh whiting or sawdust on the panel and gently push it against the cement under the leads. This begins the setting process and keeps the spreading cement from sticking hard to the glass or bench.

Adding cement to second side

Turn the panel over to cement the second side the same way as the first. If the panel is a large one, you may want to use a board to support it in these early turning stages. No gaps can be tolerated in the cementing. Cement leaking out the other side is good evidence that all the gaps between the glass and the came are filled. Again, after cementing, sprinkle new whiting/sawdust over the second cemented side and rub it gently into the exposed cement.

Scrubbing second side

Adding whiting

An illustration of the need to ensure the cement is well scrubbed under the leads comes from an occasion I had to repair a panel made by a client's friend several decades ago.  It was cemented by pushing commercial putty under the leaves of the leads.

This photo shows how the putty filled the space above and below the glass but not between the glass and the heart of the came.  It also shows the putty missing from the corners of the glass. 

The question may be asked about what is so important about a bit of putty missing from the edges of the glass, it is sealed along the leaves of the came. Yes, this style of cementing will seal the panel from the weather for a time. But had this glass been a window instead of hung inside, it is questionable as to how long it would have been until it began to leak - possibly only 20 years after being made. Certainly as the putty begins to break down, the moisture will rapidly find its way into the inside.

The only way to be certain that the panel is completely weather proofed is to use brushable cement. The cement is pushed under the leaves of the lead with a stiff brush. You know the fill is complete by the cement oozing out of the other side.

Part 3: Setting Up the Cement

After the pushing the cement under the cames on both sides, flip the panel over and begin a firm rubbing to push cement into the gaps between the lead and glass. Sprinkle the used dust from the bench top over the panel and rub in all directions. This begins to set up the cement by helping to provide a stiff skin over the more fluid cement. Brush until the whiting is largely off the panel. Turn the panel and do the same for the second side. Several applications of whiting/sawdust are required to give a sufficiently thick skin to reduce the amount of spreading, leaking or weeping cement.

Once both sides have been done a couple of times, begin to concentrate the brush strokes along the lead lines rather than across. This will begin the cleaning phase and also begin to darken the came. Repeat this on the other side.

After a few turnings, most of the cement will be cleaned from around the leads. Don’t try to get all of it away, you will need that colour for polishing. The glass will be shining, and any felt tip marks you made on the glass will have gone too. Clean up the dust from the panel and bench in preparation for polishing.

Part 4: Polishing Lead Cames

Use a soft brush to polish lead came. Don't pick out the cement until the polishing is done, as it provides the colour for darkening and polishing the lead and solder joints. 

Polishing with softer, finer bristled brush

The action with the polishing brush should be gentle and rapid, much like polishing shoes. If the shine does not come, you can use a very little stove blackening (carbon black mixed with a little oil) If you use a lot, you will have a big clean up job. A little stove blackening spreads a very long way.

Picked out, but not swept, polished inside

Before turning the panel a final time, put down paper or cloth, to avoid scratching the solder joints while polishing the other side. The result should be shiny a black came and solder joints that does not come off the way a final buffing with stove blackening does.

Finally, pick out any remaining cement.

Picked out outside

Resting, inside up

Rest horizontally with weather side down for traditional installations. If the panel is going into a double or secondary glazed unit, you may want to reverse this. The reason for having the smallest exposed cement line on the outside is to allow the water to run off the window with the minimum of area to collect. In a sealed unit or for secondary glazing, you may want to have the smallest amount of cement showing inward for appearances, as there is no weathering reason for the traditional method.

Rest for a day. Pick out the cement again. If the cement was stiff enough, there should be no need to do any more picking at the cement after this.

Brushes

Use stiff, but not hard bristle brushes for cementing. Nylon scrubbing brushes have a good stiffness without being too hard. Some natural bristle brushes are very hard and scratch the came excessively. In general, moderately stiff brushes with about 35 mm bristles are fine for cementing. As they do not last very long, they should be cheap, but with firmly attached bristle bunches.

Cleaning the brushes is very simple. The action of rubbing the cement under the leads with whiting causes a natural cleaning action to take place. As the bristles flex back and forward over the came, the cement is forced upward toward the handle, and then outward between the bristle bunches. Only a little effort is required to finish the cleaning: push a rounded stick between the bunches to move out the remaining cement. You now have a clean brush for the next job.

The alternative is keeping the brush in water, but this presents the problem of getting rid of the water (oil and water do not mix) before beginning to cement. As the water will emulsify with the linseed oil, it will be carried into the putty, leaving gaps in the cement when the water eventually evaporates. The cement will eventually harden, even though in water, as linseed oil cures by creating an organic polymer through oxidisation. It can also rot the wood handles.

Keeping the brush in mineral spirits does keep the brush flexible but requires drying/evaporating the spirit before beginning the cementing to avoid the residue of the spirit creating cement that is too thin at the start. This can be a really messy problem!

If you choose the “dry” method, it is important to keep the brushes free of hardened cement as it will scratch the leads badly, if not the glass also. Most brushes will only last 5-10 uses, and as they are not expensive, should be easy to throw away.

Polishing brushes should have more and finer bristles than cementing ones.  They can range from the very soft shoe polishing brushes to medium firm.  Many stained glass suppliers sell these, but a good shoe polishing brush kept clean will last for years.

Design Principles for Stained Glass

1. Designing for Strength
2. Responsive Colour selection
3. Beautiful Design Lines
4. Design Sources
5. Reworking Designs
6. Some practicalities
7. Conclusion

There comes a stage when each of us moves from using patterns developed by others to trying to realise our own vision. This is the time where, in attempting to reproduce an image from our mind or from natural and man-made forms, that we begin to encounter difficulties with the medium of glass and lead or copper foil.

There are a number of principles that should be kept in mind while designing, or at least referred to when the design is reaching its final stages. This article is an attempt to outline a number of the most important points in designing glass panels, especially larger ones. It also includes some practical applications.

Designing for Strength

Principles of Design Practice for Stained Glass, 1

The panel needs to be strong to last for a long time. Glass is a very resilient material; so is lead and solder. It would be a shame to design a panel in long-lasting materials that will not survive for long because of the design and construction. There are some things to remember about creating a strong panel.

The strength of a panel is in its glass

Glass in compression is stronger than steel. It is only when it is in tension that its weakness - or fragility – becomes apparent. So the structural arrangement of the glass needs to be such that each piece of glass supports its neighbours. It also needs to use shapes that are strong.

Avoid the following shapes:

Hour glass shapes – those where the ends are wider/larger than the middle - are very likely to crack at the narrowest part. If the shape – usually a negative or background one – is necessary, break it up into smaller pieces that make sense in the whole design. It is also possible to add details that will break up these shapes, but be careful that the details do not detract from the whole.


Exaggerated, deep inner curves will eventually crack at apex of curve. If unavoidable, you should consider adding design lines where the glass would break anyway, or moving elements closer together so they almost touch to avoid the single deep inner curve.


Thin long and tapering glass pieces are very likely to crack near the point or be covered by the lead or copper foil. Where you need to have such shapes, try drawing the lead or copper foil lines on the design. You can do this on a piece of tracing paper to avoid messing up your original design. This will show you how the finished panel may look. Alternatively, you can divide the long tapering piece of glass into several pieces so that any flexibility of the whole panel does not break the long thin piece. Short thin pieces are not so likely to be broken by any movement of the panel.

Inadvisable design elements

Lines radiating from a single point also provide weak areas because the glass is divided into long thin pieces which are liable to breakage. Break up long thin pieces of glass with suitable lines. This ensures that the length of the glass is in a strong relationship with its narrowness.

Avoid “hinges” - lines that run from edge to edge (vertical, diagonal or horizontal) – as these provide places where the panel can bend. This is why windows made up of rectangular quarries need so much support and even then over time begin to concertina. Even if the lines do not run all the way to the edge, any significantly long line will put pressure on the glass pieces at the ends of the hinges, for example, a series of formal border pieces or narrow central pieces. A hinge will be a weakness in the long term whether it survives the studio processes or not.

However, we all have seen leaded glass windows with single or multiple hinges that survive for many decades, and only as they loose support from firm cement and the ties to the saddle bars break away, does the panel begin to self destruct. It is important to recognise where these hinges are to be able to place reinforcements on the panel. But the real solution for making a panel that will last, it is best practice to avoid designing hinges into the finished work.

Avoid complicated shapes

Don’t over-complicate the cut lines. This makes for difficulty in cutting the pieces. Also the more difficult it is to cut the pieces of glass, the more likely it is to fail by breaking after being installed.

Responsive Colour Selection

Principles of design practice for stained glass, 2

The graphic form of much stained glass means that the medium is largely about line and colour. This requires that you think about both your and the viewer's response to the colour combinations. Respond to your instincts. Use you feelings about colour and their relationships. Try different colour ways. Formal training does help, but experience develops your skills. The individuality of the piece depends on the use of your instincts about the colour. There are some checks you can make while selecting colours.

Think of colour and impact.

Hot colours tend to have more impact, as they give bright points or areas. Impact can also be created by using non-complementary colours together. If a more subtle impression is desired, use tonal variations without great contrasts.

Vary areas of colour and their proportions.

This provides interest to a panel. It avoids a mechanical symmetrical appearance, even if the design is symmetrical

Think about colour balance.

Although the colours may vary it is important that the weights of the colours are balanced so that the focus of the panel is not lost to another part because of the imbalance of the colour with the design.

Get some distance.

When you are in difficulty selecting or arranging the colour, step back and view from a distance. This is one of several techniques to enable you to get a larger or different view. Others include viewing the design through a mirror, viewing through half closed eyes, look at the design from the other end, and viewing the design from acute angles.

Use your instincts.

When something feels wrong, trust your intuition and use other colours. Colour theory is just that -theory. It is through using your reactions that the piece becomes individual.

Seek out the nuances of the glass.

The tones and textures alter the perceived colour and weight considerably.

Simplicity of line.

Keep the design lines simple when your emphasis is on colour, light and texture. This allows those qualities to dominate the panel, rather than the lines.

Coloured drawings

Always make a coloured drawing before choosing the glass as a reference. This is a rendering of your original idea. It provides a reference as you select the colours. It is something that can be altered, of course, but does provide an essential reference point.

Use the same light as the installation location.

Choose glass colours in the kind of light for which the panel is intended. This is essential, as the glass colour is subtly different in daylight, incandescent, and fluorescent lights.

Be bold in your choices of colour.

Glass artists need to be very aware of light and dark, both in terms of colour selection and in terms of density. A very thick dense glass of a dark shade of any colour will create a much more intense darkness than glass that is thinner and less dense.

Represent the light.

In terms of colour, lighter hues go where the sun shines or where the eye is to be drawn. Pastel shades also indicate brightness and light. This also can be achieved by using the pale opalescent glass to indicate where light is falling.

Represent the shadows.

A denser dark glass can be used to indicate where light does not fall, or where very little light can filter through. It can also play the part of negative space. It is also possible to consider double plating areas where more darkness is needed.

Of course, vitreous paints can be used to control the amount of light in very subtle and realistic ways.

Use chiaroscuro.

This word - borrowed from Italian ("light and shade" or "dark") - refers to the modelling of volume by boldly contrasting light and shade. These contrasts between light and dark can be used in several ways. Darkness can indicate depth of field or distance when used in a general landscape. Or, it can be used to bring a foreground out, making other elements more vivid. The key thing to remember in using stained glass is to not be afraid of dark glasses. They can very useful, even if of very odd hues of colour.

Beautiful Design Lines

Principles of design practice for stained glass, 3

Stained glass is a graphic medium where line and colour are very important. Achieving pleasing lines and forms requires practice and use of various approaches and techniques.

The two dimensional world is one of abstract thought. Work and development are the way to creativity – there is no mystical talent. Practice drawing every day – set aside time to do it, if you normally shy away from drawing as an exercise.

Study and learn from what has gone before. Look at the images and objects you admire and analyse what you like about them and why. Also consider what things could have been done differently. Consider how those changes would affect the character of the piece.

Of course, maintaining your creative attention is difficult, so when blocks occur try some or all of these things:

• Put the work aside for a day or two before taking it out and looking at it again.
• Alternatively, pin up the design on a wall where you can look at as you pass by. When you see a change to be made, do it immediately and pin it back up

Get a new perspective, e.g.:

• Turn it upside down. This will enable you to observe differences and spot inconsistencies
• Look at it in a mirror. You might see people studying still life or live subjects together with their drawing in a hand mirror to get a new perspective that will help spot difficulties.
• Put the design on the floor and climb a ladder to look at it. This provides distance and changes the angle at which you look at your design.

Remember that design tends toward realism or abstraction. You need to work on both forms, remembering that glass is a graphic medium that tends toward abstraction. Working on both forms develops your flexibility and knowledge. Having a working knowledge of both enables you to have a responsive approach to the client.

Design Sources

Principles of Design Practice for Stained Glass 4

Use the everyday visual experience and make interpretations and adaptations. E.g.,

• draw lead lines on an illustration to make it suitable for stained glass, using the fewest lines possible
• Use your photographs of interesting subjects and scenes

These may never become useable designs or cartoons, but will increase your abilities to design from the real world toward the abstract.

Make and keep sketches as personal references. These do not need to be finished drawings, just a reminder of the thing(s) that caught your eye. Many artists always carry around a notebook to record these observations. Even if you only make drawings on paper napkins, make a folder to keep these separate sketches together.

Take photos of shapes and interesting images. These can then be used later to develop images.

Make up composite images by using overlays or collage. This helps develop your compositional abilities.

Work on abstraction in your design practice:

• Study abstract representations. Dissect – decomposition is a popular word - and analyse how the work is put together.
• Use geometric design as an introduction to abstract design. This forces your attention to structure, balance and colour.

Once the distribution of the physical and visual weights is understood, this enables the jump to more free forms of abstraction.

Reworking Designs

Principles of design practice for stained glass, 5

Having created the design, you should consider re-working the designs for a variety of reasons. Some of these are:

• to save time in the later stages of the work. It all too easy in the excitement of creating a new piece to want to get directly on with making, however this often gives construction or design difficulties that have to be solved in the making, leading to compromises. In general far too little time is spent in the design stage. Time spent on the design will be more than saved in the construction and will produce a more satisfactory piece.

• to ensure the structural stability of the piece. Although reinforcement should be considered from the beginning of the design, this is the time to ensure that the piece will stand up to the use it will receive during its – expected – long life.

• Make sure the design is still structurally sound. The design should avoid long nearly straight lines with few interruptions, especially those that go from edge to edge in any direction. The lines should interlock rather than have many joins onto long lines.

• To make sure you have investigated every possibility to answer the challenges of your design.

• Reworking will enable you to maintain the essence of the design while simplifying lines and easing the labour of the construction of the panel. Often the design contains a number of lines that are not essential to the whole design.

• As you re-work the design, you can make sure every curve, dip and angle are to your liking and so improve the whole. Redrawing also helps understanding of the design and the placing of lines. It will also help in considering the placement of lead came and the widths to be used.

• It gives an opportunity to ensure that you can cut all the pieces. This is the time to look at the negative or background pieces to make sure you can cut them as well as the foreground pieces. Usually people are so concentrated on designing the main image that the background becomes too complicated to cut easily.

Make successive tracings with each change, so there is a record, allowing you to step back wards to an earlier version if necessary.

If this re-working stage leads to the realisation of design problems, there are some things that can be tried:

• Cropping the design can transform it. The focus of the design can be enhanced by removing some of the surrounding “information”. The change of proportions say from landscape to portrait can make significant differences.

• Enlarging and using only a portion of the original design can be a solution. This is similar to the cropping operation, but has the added advantage of making the pieces larger and easier to cut.

• Further simplification of background design lines can be considered. This will bring the focus back onto the main part of the image.

• Changing relative proportions can transform the design, e.g., by enlarging a busy background, it can be made simpler and easier to read the whole panel.


Some practicalities

Principles of Design Practice for Stained Glass 6

Cartoons

The traditional approach to cartoons meant three versions were necessary. One with all the drawing details, one with the cut lines, and one for layout and leading.

If you are doing a leaded or copper foiled panel without details for painting on glass two copies are the maximum required. I make do with one original, as I have no place to keep the glass pieces laid out while cutting and beginning to lead, nor do I make templates for cutting unless absolutely necessary.

Paper

The paper you need is one that is stiff enough to avoid changes in shape or wrinkling with changes in humidity. The paper also has to be robust enough to stand up to lots of movement. Cartridge paper from a roll works well, but is often seen as expensive. Brown wrapping paper is usually stiff enough, although thinner than cartridge paper. If your design is narrow enough, you can use lining wallpaper.

Tracing paper is very useful, if you do not have a light box, as you can trace details from one version of a cartoon – whether new or from an old one – into another. However it changes shape when exposed to high humidity. To transfer the cartoon to more stable or more opaque paper, you can use a pounce wheel to transfer through the tracing paper for the final cartoon.

If you have a light box you can use it to make the transfer, or you can stand at a window with the two sheets of paper taped together to trace the design onto the final cartoon paper.

Templates

If you need to make pattern pieces you will need a second copy of the cartoon to cut up. Here you need paper or card that lies flat. You may also find it useful to cover the main cartoon with a water proof covering if you are going to do a lot of grinding and fitting over the cartoon. You can do this by oiling your paper (as for stencils) or by sticking clear vinyl over the cartoon.

Transparency sketches

Use matt finish acetate .25 to .12mm thick. This will later be fixed to Perspex for presentation.

You will need rigger brushes in sizes 0, 1, 2, and 4 for doing the lead lines and other areas of graphic delineation. In using these brushes for lead lines, you want to maintain a line that is consistently thick. It is a different feeling from general image making and you may want to try locking your wrist to maintain a greater consistency of pressure.The paint for the lead lines can be a calligraphy ink or a black acrylic paint. The lead lines and all other tracing is applied to the matt side of the acetate.

Once the tracing lines are all completed, start laying the colours on the backside, the smooth side. The brushes to use are bulbous pointed sables in sizes 2, 3, 5 and 6. The application is in a "floated" versus a "stroked" manner of application. Stroking has a tendency to hasten the drying resulting in streaking. You may find this a bit of a trick at first. It is advisable to place colour throughout the design so it has time to set up and dry a bit, as opposed to putting wet against wet.

When the colour has dried, you can emulate matting on the matt side with an ebony pencil. And if you want to take out some lights, that can be accomplished with carefully placed extender. The extender is also used to make the piece transparent and to emulate a variety of textures available in glass from reamy to seedy.

When the colours are dry, mount the sketch on 3mm Perspex to stiffen the presentation, provide weight and give the presentation with some "substance”. You can also add double matt board doors hinged with smooth electrical tape to keep the lacquer colours away from sustained sun. Also when open, they support the sketch during the presentation.

When putting matting boards around the presentation sketch, they should be much wider than the drawing or water colour so that ambient light from behind is modified by a greater expanse of black or dark matting board.

"Transparency sketches" edited from emails by Richard Millard

There are, of course, a number of CAD and drawing programs available for computers which can be used to make presentations to the clients. However, I have no experience with them, so perhaps some one will give pointers on how to make use of these electronic means of presentation.

Cartooning for acute angles

When you are moving from the sketch design to the cartoon lines for panels, you can prevent some leading difficulties. If you have shapes that join at acute angles, you can alter the cartoon lines from the design to make the leading simpler.

Say you have two balls touching in the design. You can continue the design of the cartoon so the cut lines intersect or touch each other. This makes for extremely acute angles in the cutting of the cames. Two balls touching in the presentation drawing will not look the same if leaded that way. Therefore, make the edges of the balls just a few millimetres separate in the cartoon, and the cames will pass each other, just touching, retaining the appearance of the presentation drawing, rather than the appearance of overlapping.

To do this, you separate the lines by the thickness of the came you will be using for that area. If you are using 6mm came, the cut lines should be just less than that distance apart. This will allow the cames to go around each shape and the flanges of the came will just overlap. This makes for quick leading and a clean appearance.

Making copies

Using a photocopier is not always the best way to provide copies or reproduce the cut lines. At significant enlargements, there is distortion of the lines and the cut lines are much too wide to be practical cutting guides. A much older instrument useful for this kind of reproduction is a pounce wheel. These are still made and are available. The pounce wheel comes from a time before photocopying or carbon papers. It gets its name from its use together with a pounce bag. In the past the pounce wheel would make holes through the paper or card along the design lines. The paper or card is put over the material which is to have the image copied onto it. A small bag of black powder would be dabbed (pounced) on the cover paper leaving black dots on the surface below. These could then be used to trace the same image many times on what ever medium was being used.

To copy part of one stage of a design onto a new one without using tracing or carbon papers you only need to layer a new sheet of paper under the current design and run the pounce wheel over the parts you want to copy. As you move the wheel along, it punctures the top layer and into the lower layer. Normally, the puncture marks are all that are needed to be able to reproduce the original lines.

You can also use the wheel to create mirror images by running the pounce wheel over the card, turn the card over and draw using the puncture marks.

You can get symmetrical images too, by folding the paper along the centre line and running the pounce wheel over the existing line. Unfold the paper and use the puncture marks to make lines symmetrical on each side.

Avoid tapering pieces in the design.

You can't use long tapered pieces in larger panels, without modification for the structural reasons outlined previously.

Also you can't make a neat termination by joining half a dozen tapers at one point. Your piece will not look exactly what it looks like when you drew it out with a pencil. You can pencil in a termination with six points, ending at one place and it may look good, but try drawing it in with a felt tip pen almost 6mm wide, which allows for what solder or foil will cover, and see what that point looks like then. You won't be pleased with the large blob at the termination.

Conclusion

No one can teach one easy fix for everything you will encounter, so the answer starts with the design - before you cut and foil, or fit the came to the glass.

Art is not about the physical placement of what you see in your mind, as much as it is about the "illusion" you are creating that you want others to see. That starts with the design, and avoiding something that you know is going to give you a problem in building or viewing the final piece.

Cutting Glass

Cutting Shapes

Outside Curves

Outside curves are usually the easiest curve to break out. You do not have to worry about breaking the piece, as the break - if it goes off the score line - will be away from the piece rather than into it. Outside curves normally have complimentary inside curves. So on the principle of making the most difficult break first and the easiest last, the outside curve will be broken out last. Unless, of course, there is a straight line on the other side of the curve when that would be the last, as it is the most straightforward cut.

Deepest concave curve taken out

Curve on right that has both concave and convex curves is taken out second

Score started from both ends and finally tapped out

Simple curve on the left taken out

Finally the almost straight line is cut and removed

Cutting Circles

Fixing the suction cup at an appropriate place on the glass sheet

Start score at limit of movement of arm

Hold the cutter nob firmly and rotate until you hear the click of the wheel meeting the start of the score

First, score the circle, making sure that you start and stop the score line at the same point. Circles can be scored freehand or with a circle cutter.  This example shows the use of a circle cutter with a graduated arm.

Looking closely shows the scored circle

Turn the glass over - the scored line shows more clearly

On a firm, but not hard surface begin to run the score by pressing over the score  with your thumbs

Turn the glass over onto a piece of corrugated cardboard, or other surface with some give, with the score line face down. With your thumbs, press along the score line until you see the score line "run" progressively and completely around the circle. This prevents the relief scores you are going to make from running through the circle.

Continue running the score completely around the circle

Turn glass back to scored side and mate relieving scores at right angles to the run score

Turn the glass back over to the side on which you scored it. Score several lines perpendicular to the circle to the corners of the piece of glass. Gently open these scores by tapping with the ball of your cutter, or with your hands, pliers, or other tools.

Tap the relieving scores to run them to the circle

Break the pieces away from the circle without tapping it to give a cleanly cut piece of glass

 The the pieces should fall cleanly from the circle leaving you with no rough or jagged edges.

Cutting Circles from Opalescent Glass

Score as normal.

Be careful about putting too much pressure when scoring as, in general, opalescent glass does not make as much sound when being scored as transparent glasses do.

The difficulty with opalescent glass is seeing where the score is when you turn the glass over.

If you are using a piece of glass not much larger than the circle you are cutting, you can place the fingers of your hand over the score line and your thumb on the back as you lift the glass to turn it over. This gives you the location to begin the pressure to run the score. As the first part of the score runs, you will be able to follow the leading edge of the opening score around the circle.

Positioning the Circle Cutter

If you have a suction cup on the circle cutter, it will be easier to hold in place. But a three legged circle cutter is possible to keep in place too.

In both cases, one hand holds down the centre and the other operates the cutter. Make a test circle with no pressure to ensure before you start that you know the cutting bar will not bump into anything else on the bench. This also ensures that you have the circle to be cut placed appropriately on the glass.

To make the score start with the bar under your supporting arm and swing around to the other side of your arm until you hear the click or scratch indicating that you have come back to the start.

Cutting Small Diameter Circles

It is possible to cut regular, small diameter circles without buying a lens cutter. It can be done with the assistance of a Lazy Susan or cake decorating turntable.

Cake decorating turntable with circle inscribed

Draw the circle of appropriate diameter on the turntable with a compass. Place the glass on top of the turntable, and position your cutter above the drawn circle. Press on the cutter with one hand and turn the glass with the other.

Glass scored and tapped to run the score 

Steady your hand with the cutter by keeping your elbow tight against your side. This enables you to make a very good, if not perfect, circle without buying an expensive small circle cutter.

Relieving scores tapped oug
t

You will not be able to run the score by turning the glass upside down and pressing as you can with larger circles. You will need to make a number of relieving cuts to the tangent of the circle and break them away one by one. Yes, this does leave a rough edge at various places around the circle, so grozing or grinding will be necessary.

Excess glass  removed

Circle removed.  Note very sharp shard at 10 o'clock which along with other irregularities need to be grozed or ground off

If the glass is too dark or opalescent to see the line, make a template and put it onto the glass. Cut beside the template or use the template to mark the glass. Then place the marked glass on to the turntable and cut as with transparent glass.

Cutting ovals

Cartoon with oval placed on turntable ready for scoring

 This example uses a small oval, but the same process can be used for large ovals too.

Scored and run with one relieving score placed

When scoring large ovals, the same procedure as for glass circles can be used.  Simply turn the glass over and run the score with your thumbs as for the circle.  No tapping will be necessary.

Small oval broken out from the glass

Cutting concave curves

There are several methods that can be used to break out extreme inside curves. In all the cases you should retain a significant amount of glass around the edges of the curve. You should make this most difficult cut the first on the piece. If it fails, you may be able to move the glass a little and score again, without loosing too much glass.

Glass scored along the concave line on the right

Relieving scores made and the first piece taken out

Further crescents of glass taken out

Next to last crescent taken out

Last crescent taken out in several pieces

To accomplish inside cuts by using the hand breaking method and/or pliers method, you must first score according to the cartoon line. Then you can make a series of concentric scores. Gently run the primary score line so any break does not run beyond this. Remove the graduated concentric scores in sequence.

You can also accomplish this type of cut by using the criss-cross pattern of score lines instead of concentric scores. First you must run the score of the curve to avoid the criss-cross lines from running beyond the curve. Then you begin to take out the little pieces from the waste area.

Another method is to score and run the curve, and then score a number of small crescents in the waste area, looking like fish scales or the fan type of paving seen in some European cities. Pull out each small crescent working toward the main curve.

Deep inside cuts can be assisted by using a lazy susan – a turntable affair, similar to a cake decorating turntable.

The first question you have to ask yourself is whether you should make such deep inside cuts or redesign the piece to avoid creating such fragile shapes.

OK. You have decided to go ahead with your plan in spite of good advice. Put your cartoon onto the turntable and the glass over it. If the glass is too dark or opalescent, make a template and mark the glass. Adjust the starting point, put one hand on the glass and cartoon, and turn the glass instead of yourself to get round the score with ease.

Then you can begin the task of breaking out the glass from the score line as described above.

Cutting thin strips

Cutting thin strips of glass such as used in Mission Style patterns and precision fusing projects requires skill and persistance. For transparent and translucent glass you can arrange a right angle guide on a board and tape a piece of lined notepaper to the jig. Use a cutting square and move it right along the lines on the note paper making four or six scores at a time and then breaking on the last score first and then every other score, and then each one in half.

Another method is to use the edge of the bench as a guide. With a small adjustable carpenter’s square, you hammer in nails at the predetermined width (plus half the thickness of the cutter head). Align the glass to the edge of the bench between the nails. Place a straight edge against the nails and score. This gives strips of the same width every time, but works best with strips of 10mm (3/8”) or more. This is illustrated in the processes section. 

The thinner the strips are to be cut, the more important it is to make the scores and then divide the scored sheet in half - the two halves in half each - the 4 quarters in to halves, etc, until you are down to the piece that only needs to be divided in two.

Breaking Apart the Last Two Thin Strips

For multiple thin strips of even widths, score all the strips first. Then break all the scored strips off the remaining sheet as one piece. Start the breaking process by breaking the scored sheet in the middle, then in the middle again, until there are only two to break apart.

Strips scored and broken from main sheet

Breaking pairs off the scored sheet

Cut running pliers are most useful until the last two thin strips are to be divided.

At that point use two breaking pliers to hold each side of the two pieces of glass. The noses of the pliers should almost touch on either side of the score line. Apply pressure in a downward pivoting motion to break the pieces apart.

Breaking Tapering Pieces

Breaking thin pieces of glass can be tricky, but there are a few things you can do to help direct the break the way you want it to go.

Tapering piece scored

Broken from main sheet

Relieving scores made alongside curved and tapering pieces make the breaking more certain. A relieving score is one that is in addition to the primary score. This additional score will allow you to break the thin or tapering piece from the larger sheet safely, and then go on to break out the delicate piece.

Relieving score broken away

The object is to always be breaking away less glass than is retained. The use of two breaking/grozing pliers, one on each side of the narrow pieces gives more even pressure than fingers or cut running pliers with wide jaws.

Score run started from narrow end

Running score from blunt end

Completed break

Rehearsing Special Cuts

It is important to remember the basic tips as they become even more important with difficult cuts:

• Keep an even/constant speed during the scoring
• Make sure the cutter is vertical – eye the cutter from top to wheel to cut line
• Stand behind the direction of the cut line
• Use your body to turn, do not use wrist or arm

For difficult cuts you can increase your confidence by rehearsing the score with a feather light movement of the cutter on the glass along the score line. Make any adjustments to the placing of the glass or yourself shown to be necessary by this rehearsal before beginning the score.

Start with the most difficult score first. Any break-outs or mistakes will not waste much work or glass.

Break out each score as you make it. You can store up trouble by making multiple scores before starting to break. The score lines can run across the main piece when breaking off the scored glass. Any inaccuracies will also be magnified by making all the scores before breaking.

Cutting Bottles

Cutting bottles seems to have a fascination for many people. There seem to be three methods – thermal shock, scoring, sawing.

There are various ways to apply thermal shock to assist with breaking the bottles.

- A string tied around the bottle and soaked in a flammable liquid is a common way to apply heat. As soon as the flame has gone out, you immerse the bottle in cold water; the temperature differential should crack the glass where the string was.

- Filling the bottle with water to the level where the break is wanted and then applying gentle heat with a torch flame at that level should promote a crack.

- Alternatively, the bottle can be scored and put into the freezer for a while and then into hot water.

Scoring is the common method to start a crack.

- This is followed by tapping from inside the bottle with tools from a purchased kit or home-made tappers – a metal ball on the end of a curved piece of metal.

- The score line can also be the preliminary step in the application of heat or cold.

These provide the cleanest edges to the cuts. However there is quite a high failure rate using these methods.

Sawing is method that provides a higher success rate, but is wet, and leaves rough edges to the cut, requiring further cold work.

- Band saws designed for glass can be used, but usually do not have a high enough throat to allow the thickness of the bottle to pass through.

- Most tile saws cut from underneath, so rotating the bottle can lead to a cut completely around. This requires a lot of skill to do free hand, so you need a jig to keep the bottle at right angles to the blade and the bottom the same distance from the blade while rotating the bottle all the way around.

Cutting Flashed Glass

Some recommend cutting flashed glass on the clear or non-flashed side. This is based on the idea that the flash is only laminated to the main body of glass. My view is that flashed glass has proved to be very stable over many centuries, and so is firmly a part of the whole sheet.

What is more important is to observe that flashed glass often has a bow. If you place the glass on the bench, you may find that it rocks or sits up from the bench. If you cut the glass on the convex side, that is the side which is not resting on the bench except at the edges, you may find that you break the glass during the scoring, unless you are using the lightest of pressures. It is more certain to get a good break if you score the glass on the concave side - that is where the edges are slightly raised from the bench. So the important element in deciding which side to cut is to score the concave side whether that has the flashed colour or not.

This does not occur with all flashed glasses, and is more important on large sheets than small ones. On the small ones, the curvature is so small as to be immaterial.

Preventing Chipping When Using a Tile Saw to Cut Glass

One of the most common problems in using a tile saw to cut glass is the tendency for the saw to chip the edge of the glass as it completes the cut. This occurs when the blade of the saw has less glass to cut through. Excessive and uneven pressure and the lack of support cause this break-out.

It's possible to improve the quality of the cut by slowing down and pushing the glass through the blade more gently, but this seldom solves the problem completely. Pushing equally on both sides of the cut is also important to minimise the break-out.

One solution that does work is to provide support for the end of the bar. This adopts a woodworking method for preventing splintering at the ends of cuts.

Use a scrap length of pattern bar or other thick glass. Place it against the glass being cut. As the blade emerges from the glass being cut, hold the two pieces firmly together and continue cutting. The blade should immediately engage the second piece of glass. Once the saw blade entirely clears the first piece, you can turn off the saw and remove a chip-free slice from the pattern bar.

You'll need to trim off the ends of the scrap piece from time to time, but you can use the scrap over and over until it becomes too small to do the job.

This works best with a tile saw where the blade is below the cutting surface. When you use an overhead saw, the breakout is much rarer.

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