The Glassy State

• Glass is a state of matter.
• Glasses combine some properties of crystals and some of liquids but are distinctly different from both.
• Glasses have the mechanical rigidity of crystals, but the random disordered arrangement of molecules that characterises liquids.
• Glasses are usually formed by melting crystalline materials at very high temperatures. When the melt cools, the atoms are locked into a random (disordered) state before they can form into a perfect crystal arrangement.

The complete description can be seen at the Corning Museum of Glass

Smooth Solder Beads

Good smooth soldering occurs when the temperature of the iron is correct for the job and the solder being used.

The problem of bunched up solder or peaks as you lift the iron from the solder is caused by the iron being slightly too cool for the job and the solder being used. Looking at the conditions causing the problems may lead to a better solution.

If the problem is caused by the iron being slightly too cool to let the solder flow properly, this can be caused by a number of things.

• If your iron is too low power, you may start out well and have the problem develop as you solder.
• If your iron is high enough power and you're using a 'rheostat' or dimmer controller, this has the effect of lowering the iron's power and the problem will occur as above.
• 50/50 (tin/lead) solder requires a hotter iron than 60/40 (tin/lead) solder to keep the molten metal flowing properly.

The best possible soldering iron controller is a genuine temperature controlled iron, where the iron’s controller maintains the tip temperature by applying full power to the heater when the tip cools slightly, but otherwise just 'idles'. If you can't get (or afford) one of these, possibly the best would be to get a higher power iron or throw away the 'rheostat' or dimmer 'controller'.

If the problem still occurs, then use 60/40 solder – which melts and solidifies in a narrower range than 50/50 - or perhaps do the soldering in shorter 'bursts', letting the iron recover for a couple of minutes before starting again.

In any case you need to match the speed of movement and the speed of feeding the solder to the iron according to the capability of the iron to adequately melt the solder.

Also you have to ensure that the foil has been properly fluxed and tinned.

Foil Pulling Away from Edges

If foil is pulling away from the glass on the perimeter of pieces, there are several things to remember.

Clean all the edges and surfaces just before foiling. This ensures there are no oils to interfere with the contact adhesive of the foil.

Avoid hand creams just before foiling as this increases the amount of oils getting onto the glass.

Remember that lots of heat breaks down the adhesive. So do not remain in one place too long. However the adhesive is not the element that keeps the foil attached to the glass in the long term.

Instead, think about whether the bead on the edge is thick enough to provide the rigidity required without relying on the adhesive of the foil.

Finally, think about whether an edging came would provide better support and finish to the piece.

Copper Foil Limitations

Unsupported windowsWindows without either rebar or internal support via Strongline or re-strip should not measure any more than 610mm in any dimension.

Flat work
It is not advisable to create anything over 1220mm (4 feet) by 1830mm (six feet) for a window installation even with re-inforcing bars. All such large copper foiled windows need an exterior piece of safety glass flush against the stained glass. Alternatively, split the window into smaller panels supported on “T” bar.

ReinforcementsAnything over 610mm square normally requires internal reinforcements with either Strongline and/or restrip. Inserting long strips of either Strongline (copper plated steel) or restrip (thicker strips of copper) in between the copper foiled glass pieces to create a "spine" and then a "grid" of internal support is necessary when dispensing with rebar (horizontal lines of brass, steel, or other stiff metals attached to the panel for structural support).

Polishing Solder lines

Before polishing, clean the solder (see cleaning tips) and apply the patina, if any.

Use a good quality furniture polish or wax. Shake the bottle well if it is a liquid, then apply liberally to a soft cloth, or good quality paper towel, rubbing all over solder. If you have a glass with a deep texture, try to avoid this all over process, as it can be hard sometimes to remove all of the polish afterwards, and it is noticeable when it dries. Alternatively, mask off the glass from the solder.

Immediately after applying the polish, take a clean, dry soft cloth or new paper towel, and begin to gently rub the solder seams. If you are using paper towels, you will need a lot of them, as they tear up quickly. When both sides have been polished, check for any missed spots, especially along the edges of your solder seams. Also check for polish residue in tight corners and along the edge of the solder. An old toothbrush often works to remove it. If you need stiffer bristles, make sure you keep this new toothbrush separate from all the others in the house.

Lampshade Pattern/Cartoon Tools

Lampshade patterns –tools for custom-made patterns.

The items you need to have for creating your own pattern are not extensive or unusual.

• Craft knife or razor blade
• Baby/talcum powder
• Fine pointed felt tipped pen (Sharpie)
• Highlighting pen
• Pencil
• Eraser
• Carbon paper
• Drawing paper
  Masking tape
• Lampshade form
• End/vase cap
  

Further design process information is here and here

Lamp Panel Dimensions

Lengths of Panels

Lampshade Pattern Construction, 3

Cut the finished template into sections (if you are using a 360 degree form)
The masking tape template will need to be cut off the curved form and laid out flat. This is easier to do if you can logically separate the template into smaller sections. To do this you need to find lines running almost vertically from the top to bottom of the template. Mark these separation lines in a different colour. Also label each section.

Remove the template(s) from the form and press it out flat
Take a craft knife or razor blade and trim away excess masking tape from the end cap mark. Do the same for the bottom edge. Carefully remove the excess and throw it away.

Prepare a section of your work surface by sprinkling some talcum powder on it, and onto your hands as well. This will help keep the sticky side of the masking tape from sticking where you don't want it later.

Using the craft knife, slice through the middle of each separation line that you marked in a special colour. Try to stay in the exact middle of the line. Be careful that you do not tear or cause to pull away the underlying masking tape as you cut through the line. Do this with each separation line.

Starting with the top edge, use the craft knife to gently pull the masking tape template off the form. If the masking tape starts to separate, stop and repair it. As each section is taken off the form, put it sticky side down into the talcum powder and press it flat. Do this for each section.

Scan/copy the template(s)
At this stage you can scan each section into Glass Eye or other image software. This allows you to:

• select and change colour/glass choices very easily
• print out or email colour proofs to the client
• keep them in an electronic form for future reference or manipulation

You don't have to scan your pattern, but you do need to make at least two copies of the pattern.

Cut out one copy and reapply it back to the form
One copy is fastened back onto the form so that you know where to put your glass pieces.

Cut out the other copy and paste it onto your glass
The other copy is cut out using pattern shears (the three-bladed scissors) and glued onto the glass for cutting.


Based on work by Christie A. Wood, Art Glass Ensembles

Lampshade Pattern Construction, 2

The second stage is to get the design onto the prepared mould and make adjustments to give a balanced and pleasing appearance

Trace the pattern onto the template
Take your design elements and trace them onto the masking tape on the form. The use of carbon paper enables you to put the design element and trace right on top of the taped mould so that the image is transferred onto the tape.

An alternative method is to use a pounce wheel to perforate the design element. The element is placed on the form and dusted along the perforated line with a bag of dark coloured powder such as powdered poster paint. This will leave a temporary trace on the form that can be changed easily, but needs to be pencilled in before too much other work smudges the shape.

Do this tracing with each design element, flipping and rotating them around so that you don't repeat any element exactly. Fill up major sections of the form using this method. Drawing the main feature first and filling with the minor elements helps provide a pleasing composition.

Fill in blank areas
Now that the key design elements are onto the masking tape template, create background pieces by linking your design elements. Use pencil, since you will probably need to do corrections. Remember, avoid creating large horizontal pieces. Larger vertical pieces are usually better. However, try to keep all the pieces of similar size.

Correct any pieces and number them
Once you are satisfied with the design, go over every line with a fine felt tip pen or other ink pen so that each is clear and distinct. Number each piece and mark colour and glass textures as necessary.


Based on work by Christie A. Wood, Art Glass Ensembles

Grinding Tips

Protect your cartoonWhen grinding a lot of pieces, you can place a piece of clear float glass over top of your paper pattern, or encase it in plastic to protect it from becoming wet. Then you won't have to grind, dry, test, and repeat. You can just grind and test, quickly grinding where needed.

Placing your cartoonAlso try to have your pattern where you are test fitting right beside your grinder, to cut down on time spent moving from grinder to pattern.

Grinder resevoir maintenanceRinse out your grinder sponge often (at least daily), and replace when it becomes deformed.

Clean out the ground up glass in the bottom of your grinder regularly with a narrow putty knife. Scrape it out into a small old plastic container with a top, and then throw the container into the garbage when it is full.

Grinder head maintenanceMove your grinder head up or down, as it is wears, to a new section. You should be able to get three or four sections out of a typical grinder head.

Copper Foil vs. Lead

The copper foil technique may or may not have been invented by Tiffany, but he certainly used it extensively in his studio. Thus it is often referred to as the Tiffany method.

It is neither easier nor more difficult than lead. However, it’s significantly cleaner because it does not involve the use of whiting or cement, which is why this technique is most often taught to beginners in North America. In Europe leading is most often taught first.

Some people deduce that copper foil must be stronger than lead because the solder goes all the way around and between each piece, but lead is still the preferred method architecturally, holding up huge weight-bearing windows for hundreds of years.

One thing copper foil can do, though, is allow stained glass panels to curve, as you can see in the multitudes of Tiffany lampshades that are still around today.

There are a few other differences from lead in the construction of copper foil panels. First, copper foil is less forgiving in that there is no channel to hide errors in glass cuts. Precision in cutting becomes especially important.

However, while cutting may be a little more difficult, soldering foiled pieces is a little easier because you can’t burn through copper foil the way you can through lead. If you accidentally apply too much heat, the solder just drips through to other side and forms a ‘mushroom’ that must be cleaned up later. Or it cracks the glass.

Finally, lead panels are usually constructed from the corner out (pieces of wood form an “L” shape and the panel is started in that corner and grows up and out). Copper foil panels are usually started inside a (temporary) wood frame that goes all the way round the panel, like a picture frame. You don’t need to start in one particular spot because the pieces aren’t going to shift within their frame.

Copper Foil Repairs

Repair or not

First consider whether any repairs should be carried out at all. Repairing can sometimes cause more damage, and if it is an older piece, finding an exact match may be impossible. So gluing may be the better approach.
If small shards of glass are missing, daylight is visible through the broken part, or sharp bits are exposed, then it should be repaired, assuming the client is willing to pay.

Starting the repair

Having decided to repair, the first action is to use fine steel wool to remove any patina from the solder around the broken pieces, on both sides.

Removing the broken glass

Next, work out the shards using a fine blade to get between the broken pieces. You should be wearing safety glasses during all the processes of getting the glass out of the piece.

In some cases in may be necessary to score the remaining part of the broken piece with your cutter in a criss-cross pattern, from edge to edge. Also try to go toward the centre of the piece from each corner while making the score lines.

Now start tapping the centre of the broken, scored piece of glass with the ball on the end of your cutter and then work out to the edges. Keep tapping the glass and it should start to fall out. When most of the glass in the middle has fallen out, take out small pliers and gently wiggle the broken shards out, one at a time. Remove all the glass possible, but you might not be able to get the glass in a tight corner.

Removing the solder and foil

Now take your soldering iron and melt off the bulk of the solder seam, slowly going all the way around the hole. Wipe excess solder off on your iron stand sponge. Do the same on the other side. During this process you will be able to remove any remaining small pieces of glass.

Apply the hot iron to the corner joint to expose the piece of copper foil that was wrapped around the broken piece of glass. With a pair of tweezers, grasp and very gently tug out that inner piece of foil while keeping the iron on the solder line to keep the solder molten. Try not to pull the foil off adjoining pieces. If some other foil does come off, then remove that entire length, scrape clean, wash off, dry, and re-apply a piece of the same type of copper foil, cut to size.

Re-flux the exposed foil lines, remove any solder blobs - particularly in any corners - with your iron, wiping excess off on your sponge again.

Replacing the glass

Taking the shape
Take your piece of glass that best matches the broken piece, and position it underneath the hole. Trace the shape of the hole onto the glass. This works best for flat panels. Curved forms usually need to have a paper template made by tracing from the back onto the paper. Cut the shape out of the paper and put it on the piece of new glass. Make sure that the grain of the new glass is in line with the original. Cut the piece out, grind to shape, doing lots of test-fitting in the hole, until it fits.

Foil
Clean any flux off the new piece from your test fittings, and apply the same size and colour backing of copper foil that was used on the piece that you removed.

Soldering
Fit your replacement piece into its place, making sure that it is level with its surrounding pieces. You might want to tape it into place. Check its position, and if you are happy with it, then tack it twice per side.
Proceed to solder it into place. If your fit wasn't perfect, or the piece is a little rough, fill in any gaps with some 50/50 solder. Let it cool, and then finish off with 60/40 solder. Blend your new solder lines with the quality of the solder lines on the rest of the piece.

Cleaning
Wash off the flux, scrub clean, and patina if required. If copper patina was used on the piece, don't worry when you apply the copper patina. It will not match if the panel is not brand new as copper patina ages much more than black patina. Wash the patina and polish it to blend the piece in.

Cleaning Solder Beads

After soldering, cleaning and drying your piece, use fine (000) or extra fine (0000) steel wool and a brass wire brush to go over all the beads. Use the brush first if you want to use it, and follow with the steel wool, since it will provide fewer scratches. This helps remove any leftover flux that on solder lines.

Omitting this step increases the chances of developing whitish blotches later on the solder lines. However, including this step makes a better base for applying the patina, if you are using any. After using the steel wool, use a soft brush to remove any residues from the steel wool, brush, flux or solder.

Choosing Copper Foil Widths

Width of the foil relates to:

Glass thicknessThin glass requires thinner foil to maintain a neat solder line of about 3mm. Thicker glass requires thicker foil to maintain the same width of solder line. So 2mm glass would require 4mm foil, and 3mm glass would need 5mm foil.

Glass textureHeavily textured glass usually needs thicker foil, as the thickest part of the glass is greater than the thickness of average glass. This requires a little experimentation to get the one you like best, but usually is one step up in thickness from your usual. Remember you are looking at only one half of the resulting solder line thickness on each piece of glass.

Desired width of solder lineThe desired width of the solder line will also affect the choice of foil. If you like a thin line of solder, you should choose foil that is only 1 or 2mm wider than the thickness of the glass. This will give a solder line of 1 or 2mm wide. Be careful when choosing a thinner width. You still need enough foil on your glass to maintain the strength of the solder bead. If you like wider lines, a foil that is 3 or 4mm wider than the glass thickness will give a 3 to 4mm wide solder line.


Of course is possible to trim the copper foil to be thinner after foiling.  This can be to even up the line, or to thin it.  Gentle pressure with a sharp craft knife will cut the foil to the width you want. You may want to do this when all the pieces are assembled before soldering.  This gives you the opportunity to see how the width of the resulting solder line will be.  It is also the time when you can see what the line of the solder bead will be and make adjustments before begining the the soldering.

Choosing copper foil Thickness

Foil comes in different thicknesses as well as widths. Thinner is easier to form round curves, but tears more easily. Thicker is more robust, but crinkles up more on inside curves and so needs more burnishing. Mostly it is personal choice on what is easiest to work with.

Choosing copper foil backing

The question most people want to know is why there are different colour backs to the foils. The answer has to do with the finished piece, and only matters if you are using transparent glass. If you are using opaque glass that you cannot see through it doesn’t matter which type you use.

The backing should be of the same colour as finish to the solder lines. Since you can see through transparent glass, you will be able to see bits of the back of the copper foil, especially at certain angles. It would look peculiar to have a piece with a beautiful black patina, only to catch glimpses of copper when you are looking at it.

Therefore, if you are planning to patina your piece black, use black-backed copper foil. If you are planning on leaving it silver, use silver-backed copper foil. If you are planning to patina it copper, use copper backed copper foil.