Construction

Because early glass could only be produced in small panes, a technique was developed to combine them into a window using lead. This uses strips of "H" section lead "came" around the edge of the glass and joined with solder. This forms a girded pattern formed by the shapes of the glass panes. This is still the method employed today only using modern extruded lead came.

Lead is a soft malleable metal (it can be scratched with a fingernail). It is available in a variety of widths and profiles but normally we use sizes between 5mm and 12mm.

The first stage in producing a leaded light or stained glass window is the drawing of a pattern called a "cartoon". Traditionally this was done by hand but we now have pioneered the use of the computer and a plotter which creates a more accurate design.

The glass is then cut by hand to match the shapes on the cartoon. When all the glass is cut a outside strip of lead (this is usually wider than the inside lead to compensate for the depth of the frame rebate) is layed out on the workbench and then glass inserted, with pieces of lead and glass fitted together until the window is built.

The joints between the lead are then soldered together, forming a strong lead latticework. After leading the window is sealed by brushing a cement into the gaps between the glass and the lead. When dry the window is cleaned of excess cement and the lead work polished.