Pattern and Stained Glass Cutting: When cutting stained glass for a leaded
stained glass
window, a 1/16" allowance must be made for the "heart"
(center) of the lead came. This is normally done by using 3-bladed
pattern shears for lead to cut out the pattern templates. Once you have
an accurate pattern with lead allowance, cut the stained glass in the usual
manner.
Tools, Terminology and Safety: "Came" is the term
for the extruded lead channel used to form the framework of a stained
glass window. Lead came comes in two basic shapes, each one named after
the alphabet letter it looks like. "H" came is used to join
two pieces of lead together; "U" came is usually used around
the outer edge of a stained glass window, unless the stained glass window is to be installed into an
already existing window frame. If this is the case, "H" shape
is used so adjustments to the outer edge can be made later if necessary.
The outer profile of either came can be flat "F" or rounded
"R". Thus, a 1/4" RH came would be an "H" shape
with a rounded profile measuring 1/4" wide.
There are a few specialized tools and supplies required. A fid (lead
opener) is a pointed plastic or wood tool used to open the lead channel
and to clean up after glazing. A lead vise is used to secure one end of
the lead strip while stretching. Horseshoe nails are preferred to hold
stained glass in place while leading. A flush cutting lead nipper (dyke) is
normally used to cut the lead; a sharp knife can also be used.
Handling lead poses a risk of lead poisoning if certain safety
precautions are not followed. Lead cannot be absorbed through the skin -
only through ingestion or an open cut. Follow these basic safety rules:
Always wash hands well with an abrasive soap and water after working
with lead. Never eat, drink, or smoke while working. Always bandage any
open cuts on hands and fingers. Keep children away from work area.
Lead Stretching: Lead came must be stretched before using it.
This will help straighten out any kinks and also stiffens the lead. Lead
usually comes in six foot lengths. Secure one end in a lead vise and
grip the other end with a pair of pliers. Pull slowly and steadily until
the lead has stretched 3" to 6". Then set aside on a flat
surface for later use.
Workbench Setup: Tape your assembly pattern to a work board or
benchtop. Nail wood strips on the bottom and left sides just outside the
perimeter lines on the pattern. The wood strips should form a 90 degree
corner; use a square to check and adjust wood strips if necessary. A
square corner is very important.
Assembling the Stained Glass Window: Assembly will start in the lower left
corner and work outward to finish in the upper right. Lead is a soft,
pliable metal easily cut with nippers. Best results are achieved by
cutting through the "channel" side (with the heart in sideways
or horizontal position). The nippers tend to crush the lead when cutting
with the heart in a vertical position.
First, cut strips of lead for the bottom edge and the left edge - cut
them 1/2" longer than the pattern. Place the strips on the pattern,
butting the joint in the corner. Use a couple of horseshoe nails to hold
the lead in place.
Locate the piece of cut stained glass for the lower left corner and fit it
into the lead came snugly. Make sure the pattern lines are visible just
beyond the exposed edge of the stained glass - if not, tap the glass slightly
with a wood block or the flat end of a lead knife until it fits. Recut
the stained glass if necessary. When it fits just right, use a horseshoe nail to
hold glass firmly in place. Next, cut a piece of lead to fit the right
side of your corner glass piece. Cut it slightly shorter than the
stained glass to allow for the lead overlap. TIP: Cut a short piece of lead to
use as a gauge to help determine exact length. Then fit the next piece
of stained glass into the space just to the right of the corner piece. Use two
horseshoe nails to hold it in place.
Continue working in this manner, moving towards the upper left. Be
sure each lead piece butts tightly against the adjoining pieces. Use
plenty of nails to hold all the front line stained glass pieces in place as you
go. If the pattern contains any long straight lines, use a single piece
of lead rather than many short pieces. As each stained glass piece is fit into
place, remember to check it against the pattern. Seemingly minor
problems can multiply into big ones as the window "grows" due
to oversize pieces.
After the last piece of glass is fitted in place, make sure that all
perimeter pieces on the top and right sides are just inside the
perimeter pattern lines. Next, cut lead strips for the top and left
sides. Cut the top piece a little longer than the window, fit it along
the top edge making sure that all stained glass is inside the channel, and
secure it with a wood strip. Then cut the left side came to fit between
the top and bottom cames, butting all edges. Secure the left side with
wood strips and nails.
Soldering: The assembled panel must now be spot-soldered at
every lead joint. Soldering should be done in a well ventilated area -
outdoors or in a garage is best. If indoors, open a window and run a
fan. All lead came should be clean and shiny before soldering begins. If
lead is not shiny, use a soft wire brush on all joints to remove any
oxidation. Plug in your soldering iron and let it warm up for 5 minutes.
Next, use a small paint brush to apply flux (liquid or paste) on each
joint. Flux is a cleaning agent that allows the solder to bond with the
lead came. If you forget to flux, solder will not stick to the lead. To
begin soldering, first test the temperature of your iron by touching the
tip on a scrap piece of lead; if it instantly melts, your iron is too
hot. Use a rheostat to lower the temperature or unplug the iron until it
cools down. The iron should be hot enough to melt solder quickly, but
not so hot that it melts lead in less than about five seconds. After
adjusting temperature, uncoil a few inches of solder from the spool and
hold the end of the solder on top of a lead joint. Position the flat
side of the iron tip directly above the solder. Touch the solder until
it melts, then pull the iron tip straight up. The iron should only be
touching the joint for a second or two - any longer can melt lead came
or crack glass. Continue this process at every lead joint. If the solder
is not smooth, just move on and come back to it later when it is cool.
Brush any rough solder spots with a little flux and touch with flat side
on iron tip until solder "puddles", then lift iron straight
up.
When all lead joints have been soldered, carefully turn the panel
over and solder the back side. For large windows, sandwich window
between two pieces of plywood before trying to flip it over to back
side. When soldering is complete, remove flux residue by washing panel
with warm water and soap (or a commercial flux remover like
"CJ's").
Glazing and Cleanup: Applying a glazing cement is the final
step on a leaded window. The cement is what makes the panel rigid and
strong - without it, a leaded window is floppy and won't last long. TIP:
Wear old clothes - this process is messy. You will need a pre-mixed
glazing cement such as "Inland Cement", whiting powder
(calcium carbonate), and two natural bristle brushes (or one brush cut
in half). Stir up the cement until it has the consistency of cake
frosting - takes about 10 minutes. Then dip a brush into the cement and
use the brush to apply the cement to the window panel, brushing in a
circular motion to work the cement under the edges of the lead. Don't
worry about what a mess it looks like at this stage. Keep brushing until
all the lead came has been cemented.
Next, use whiting powder to clean up the excess cement. Wear a
respirator during this stage. Spread a light coating of whiting over the
entire panel. Use your clean brush in a circular motion again, brushing
against the lead came and allowing the whiting powder to soak up the
excess cement. Brush away any dry clumps and continue brushing - apply
more whiting as needed. When the cement is cleaned from the glass, keep
brushing to burnish the lead cames and polish the glass. Then flip over
the panel and repeat the process, starting with cement application.
After both sides are glazed allow glazing to set-up for a few hours (but
no more than 24 hours), use a fid or pointed stick to trace (pick)
around each piece of glass and clean away excess cement. Be sure the
window is clean - once the cement dries, it is extremely difficult to
remove. Allow the window to dry for at least 48 hours before moving.
Small amounts of cement may ooze out from edges - use a fid to clean up.
As a final step, the patina and wax may be applied.