Stained Glass Panel Work
If you have read my previous posts you will have some idea of the complexity of designing and making stained glass panels that are pictures. Also it is to be remembered that I am discussing unique stained glass work – not factory processed, reproduced by the hundreds, coloured glass panels.
The pieces of stained glass that go into a design can take a lot of work per piece.
Now consider the hourly rate you might be willing to pay your plumber or your electrician. Consider also that plumbing and electrical works, by comparison are quick work. Then consider what you would be willing to pay your glass artist – and lets hope its at least as much as a plumber or electrician per hour. Why? Because a stained glass panel is an artisans job and is worth more than a trade electrical or plumbing connection. The finished panel you end up with is something that will appreciate in value.
A Few Years Ago
In 2010 I designed and made two stained glass panels for an interior door. The door was the type with two long vertical panels side by side to the top part and solid to the bottom part below the door handle. Each panel was 36″ by 9″ inches (910mm by 230mm). At this time the cost for each finished and installed stained glass panel was just over £800. So £1600 for the whole job.
What Stained Glass is Not
Stained glass used in stained glass pictures, is not surface coloured glass. By this I mean it is not a picture outline painted by use of a black pigment, nor is it painted with colour. There will be no acrylic, no alcohol based paint, or other form of paint on the stained glass panel to obtain the effects of the design. The design is made with lead and real stained glass. Real stained glass being a sheet of glass where the colour is added in the glass at the fireing .
I note here that many old church windows are painted (on the glass) to create the desired picture/faces, – I know.
My definition of stained glass is: – ‘NO PAINT’ – – – ever.
Stained glass colours in the glass are made by using various chemicals; for example oxides of metals in the glass as it is heated and the molten glass is made into sheets. Some colours are much more expensive to make than others.
Generally, pinks and purples are more expensive. Pure reds are definitely more expensive. Depth and clarity have a lot to do with the higher cost of many colours.
Pinks, purples, and reds can be made from what is called a colloid; this is a colloid of gold. A colloid is a substance where the particles are microscopically small in size. A colloid has particles of the chemical element concerned of not larger than one millionth of a metre. The colloid particles in size are 1 micrometre to 1 nanometre, i.e. 10-6 to 10-9 metres.
As well as the chemical mix, It is the physical size of the particles that actual split the light passing through the glass to produce the colour. Today a red glass is made by adding gold salts or colloidal gold to molten glass.
Old church windows (pre- Henry VIII, the king of England, who ordered the destruction of many churches) had a red stained glass whose depth and clarity was supreme. Glass makers and scientists have failed to reproduce the excellence of this glass and historians have failed to find any record of how it was made and what chemicals were in it.
It remains a mystery as to what was in the red glass for the process of its making and production, always considering the state of “industry” at the time.
Repairing Cracked Glass
If we imagine a crack in a cell of stained glass in the centre of a finished glass panel; trying to repair such a crack is never easy. There are a few options: –
- The first option is to look on the damage as a form of ‘patina’ (if its small); therefore do nothing to it.
- Dependant on the severity and size of the crack, the second consideration might be to use a car windscreen repair liquid to mend the crack. Some of these liquids may almost make the crack disappear (again if its small). I would recommend trying this as it is the least traumatic method for the glass panel. There are also other forms of glue for literally glueing the glass, which can work well for small chips or pieces of glass. If it doesn’t work, you can always go on to the final method.
- Finally trying to repair a crack will require the removal of the broken glass, which means folding back the lead. If the glass is not broken so that some of it has fallen out; then break the glass carefully to enable its removal. Remove all the glass from the broken cell. Remove the broken glass may require the slow and careful removal of the cement holding it in place. Remove some of the cement to ease the glass lose; but not necessarily all of it at once. Damage to surrounding cells could occur if care is not taken. Once the glass is removed, the top side of lead surrounding the cell must be slowly folded back so that a new piece of stained glass can be installed into the cell. It is easy to crack the glass in an adjacent cell(s) when doing this. Folding back of the lead can take hours. Folding back the lead also enables all old cement to be removed.
Removing Part of a Soldered Butt Joint
The folding back of the lead is one part of the repair (see next). However at every joint or corner in the shape of the stained glass piece, means the lead that has been soldered there may need a cutting job to be done. The lead at this point is comparative very tough. But in order to install the glass, this soldered joint may (but not always) need to be got out of the way. Really the only way to do this is to melt the lead soldered joint with the soldering iron. This takes real skill in not over-doing it, which if it happens will be very difficult to repair without it looking a mess. You could accidentally melt the lead channel which is very difficult to repair and keep the result looking neat.
Cutting the lead away from the soldered butt joint is another option. It is possible to pare it away with a Stanley knife. Carefully. As usual the exercise is dangerous to the rest of the panel. Not my recommended method.
The method I personally use is a machine called Dremel made for model makers. This machine has all sorts of tiny attachments for cutting away material and smoothing and finishing the result. Again – care is required, but the result can good to excellent.
Folding-back
Folding back the lead will be essential for installing a new piece of glass that you will have cut out again to the same shape as the old piece. Not all sides need to be folded back; for example if you had a cell of glass of roughly five sides, you would have to fold back four sides and the last side could be merely expanded using the channel tool (see previous post) to enable the new piece of glass to be slid into place.
Warming
Obviously lead is more pliable the warmer it is. To warm the lead prior to or as you are folding the lead back you need to create some warmth or heat on the lead. To do this there are two tools: –
One is a small pencil flame gas blow-torch with a small flame spreader, which in itself can do greater damage than you may already have. If the flame passes over any part of the glass in your panel it will crack it. This is caused by sudden expansion of the glass due to heating in one place. So enormous care and practice needs to be applied to the use of this tool. This tool is best used for helping to fold the lead back down.
Another method of warming is the use of a soldering iron, which is by comparison much safer. This iron will be a lower wattage than the one used for soldering the lead joints. If you can find/source it, a tip that is shaped like a small loop or slow curve, specifically designed for warming, is ideal. This tool can supply heat to the spot needed i.e. the point in the lead that you are folding back. Generally this is done by stroking the lead with the tip of the soldering iron. Unfortunately the use of a soldering iron to do this heating can be very slow, so lots of patience is required. The last thing you want is to accidentally begin to melt the surface of the lead came itself.
Installing
Once the cell is clear and clean; install the newly prepared piece of glass onto a bed of cement to the lower unfolded edge in the folded-back lead channel. Allow the cement to set to a solid hardness that is still workable. You will need to have inserted tiny spacers to hold the glass at the right level in this underside cement, much the same way a tiler uses them when tiling a wall. The spacers can be made from match sticks pared down to the right thickness. Then start to very very gently fold back down the top lead to hold the glass in place. Again you may need to use some form of spacer to ensure the lead leaves a consistent space for cement filling to the top side. Make sure that the folded-back lead is level, undamaged by this traumatic operation and still leaves a gap for filling with cement. Now fill the top side of the glass cell lead channel with cement.
Go to the underside of the panel and pare off any excess cement to produce a clean finish that can be allowed to harden completely. Fill in any tiny holes left when removing spacers. Then turn the panel back to the top side. When the top side cement is hard enough, scrape off any excess to make a smooth filling in the channel of the lead and leave to harden completely. Tamp both sides down with the smoothing tool. Once hardened on both sides of the panel, clean off any left over cement from the glass cell and polish the glass.
Job finished.
Cost of Repairs
This sort of work is in my opinion unpriceable. The replacement of glass can take many hours and the bill could be hundreds of pounds/euros for just a single small glass cell just dependant on the level of difficulty. In fact the smaller the cell of glass to be repaired, the more difficult the repair might be in some cases. Doing the repair is also fraught with danger to the rest of the panel.
Also See Post entitled: – Stained Glass – Cutting of the Lead
