From design to dedication.
When we receive an inquiry for a new window the first thing we need to find out is it’s size, it’s intended location and of course what kind of window is wanted. Some people have a firm idea of what they want from the start and others are less sure. The starting point may simply be a design style such as Art Nouveau or modern or a Victorian design to compliment a Victorian building. It may be a whole bible story or just a few words, we can even start with what kind of mood you would like the window to create; calming, inspiring, sombre, uplifting etc. When starting a window from scratch the possibilities are endless.
After some discussion we can gauge the complexity of the window and from this provide a price guide. If is within the clients budget then the design process begins. To illustrate the the whole process from design to dedication this article will follow the creation of the St Paul window for Paulsgrove.
Before design could really begin a good deal of research was necessary. In this case that involved finding out the details of St. Paul’s life, the events which shaped him and the journeys he made.
After more discussion and input from the clients the basic structure of the composition is decided upon and a full size cartoon of the window is produced. Many improvements are made to the design at this stage and the design of the finished window rarely differs from the completed cartoon.
When the clients are happy with the full size cartoon copies have to be made of it and a paper template is produced for every single piece of glass in the window. In the case of this window there are around 600 pieces of glass. The next phase is selecting the exact colour of glass to be used and cutting the necessary shapes from the paper templates. A great deal of accuracy is needed during the cutting of the glass, each piece must match the template exactly. Much care is also taken in selecting the perfect colour for each piece from the hundreds we have in stock.
When all the glass has been cut the painting, shading and etching processes begin.
Drawing around the paper stencil on the selected piece of glass
Using a glass cutter to cut out the shape
Acid etching is done by protecting certain parts of the glass a resist. The unprotected areas are then exposed to hydrofluoric acid by placing the glass in an acid bath. The acid eats away at the surface of the unprotected glass altering its thickness and therefore strength of colour. This technique works best on flashed glass. Flashed glass is a sheet of glass made of a thick layer of clear glass and a thinner layer of coloured glass. By etching through the coloured side with skill and care it is possible to produce a range of shades of colour, from the original colour (before etching) getting progressively lighter through to clear when the coloured layer has been removed completely.
The painting of the glass is painstakingly carried out by hand. When each piece is finished it must be fired in the kiln. This permanently bonds the paint to the glass. Some pieces will require this process to be repeated several times.
When all the painting and etching processes have been completed the window is reviewed and perfected. The photo on the right shows all the pieces of the centre panel laid out on a clear glass table. A mirror on the floor beneath the table shows how the window will look when complete and held up to the light.
When all work to the glass is finished the window can be leaded up. This involves cutting to size and bending lead came around each piece of glass. Much care must be taken in this phase to insure that each piece in in precisely the correct position so everything lines up as it should do. The flow of the original design is carried thorough to the lead lines. Wether each lead line will continue or brake at intersections where lines cross must be planned in advance to create the best aesthetics. This window uses a range of different lead widths, from 5 mm wide to 12 mm wide. The different widths are used to emphasise certain dynamics of the composition, leading the eye around the piece. As this window comprises of three panels continuing lines must correspond between panels.
When a window has been leaded up completely every join between lead lines must be soldered on both sides. Soldier is a mixture of 50/50 lead and tin. We use Gas powered soldering irons as you can see from the photos. We also use a tallow wax flux which must be removed with a stiff brush after soldering
Lead light cement is forced into every gap between the lead and glass after the soldiering process. The cement is black in colour and a thick consistency. It is carefully applied to every part of the window on both sides. Whiting is then brushed into the cement and any excess removed with a sharpened piece of wood. When the cement dries it not only makes the window waterproof and read to face the elements, it also improves the strength and rigidity of the window.
The cementing up of the window is a messy process so after the cement has had time to partly set (but before it hardens completely) the windows are thoroughly cleaned and polished. All remaining excess traces of cement are removed with a wooden scraper and brushing with black polish cleans the glass and blackens the lead while removing dirt.
After final cleaning and polishing the window is nearly complete. All that remains to be done is to fit metal strengthening bars to the window. These will help to prevent damage from any flexing of the window in high winds and also prevent any bowing of the window over time. In this case the bars are bent into a shape which maintains strength but is subtlety integrated into the window design. Copper wires are soldiered on to the lead of the window and they are neatly wound around the bar to hold it in place.
Left and above; copper wire ties. Right;bending steel bar to follow lead line on window.
The final stage is the fitting of the window. In this case the window has been fitted into a custom made wooden frame and we have fitted clear UV stabilised poly carbonate protection to the outside. To learn more about window protection please click here.
Various ideas get experimented with in sketch books and then small watercolour designs are produced in which the of colour pallet and composition start to come together.