THE LEADING TECHNIQUE
The process of interlocking and assembling
pieces of glass together using lead came is called
"leading". There are two common shapes of lead came
used. "H-"shaped lead has a double channel and is
usually used between two pieces of glass. "U-"shaped
lead has a single channel and is used for the outside perimeter
of panels, mirrors, shades, suncatchers, etc. The face of either
type of lead came may be rounded or flat.
Lead came is commonly sold in six-foot
lengths. Today, much of the came sold is not pure lead. It is
alloyed with several other metals to make it stronger, easier to
solder, and to prevent it from oxidizing quickly.
A 1/16" allowance must be made between
each piece of glass if you are leading your project. The heart
width of H cames is 1/16" thick. Whether you use the
traditional or the paper pattern method of cutting your glass,
you must allow for this 1/16" or the size of your panel will
grow when the glass is assembled.
The thickness of the glass you have chosen
and the project you are making are important considerations in
your choice of lead came. Flat H leads are generally used as
perimeter leads in windows, while the round ones are used to lead
the inside seams of a panel or in lampshade construction. If you
are going to border the perimeter of an unframed piece, use U
channel. The most common leads used for building panels and
shades are 3/16" or 1/4" round H and 3/8" or
1/2" flat H. These measurements refer to the size of the
face of the lead came. The size of the channel is standardly
3/16" which will accommodate most types of glass.
When strength is a critical factor, lead
came with a hollow heart into which steel rods are inserted can
be used. Channels made of zinc are also available and widely used
to reinforce and add overall strength. Both of these types of
came must be cut with a hacksaw.
STRETCHING LEAD CAME
Before lead came is used, it must be
stretched. Stretching removes the kinks, straightens the lead,
and makes it more rigid. A lead vise is a handy inexpensive
gadget that does the job well, but a regular bench vise will
suffice. To stretch your lead, first insert one end firmly in the
vise. Holding the other end with pliers, pull the lead just
enough to get it straight. Don't stretch it too much or the
channel will become too narrow and the glass will not fit in it.
TOOLS FOR THE LEAD CAME METHOD Listed here are the tools
and supplies you will need for the lead came method. Some tools
are optional, while others are absolute necessities. Optional
items are marked with an asterisk (*).
||*lead pattern shears
||*circle or lens cutter
||small wire brush
||*diamond bit grinder
||lathkin or fid
|ruler or straight edge
||*light box or table
|stiff bristle brush
||3/8" sharpened wooden dowel
||whiting, Plaster of Paris, or
||oaktag or file folder
||flux and brush
||glass marking pen
THE LEADING PROCESS
- Step 1. First tape the working
copy of your pattern to your work surface. A good surface
for leading is soft particle board or plywood. Then frame
your drawing with two adjacent strips of wood nailed to
your board at a 90 degree angle.
- Step 2. Stretch your perimeter
lead and cut two strips 1: longer than the height and
width of your panel. Place them along the wood strips
inside the frame. Butt them up against each other or
miter them at a 45 degree angle.
- Step 3. You will begin leading
in the inside corner of the wooden frame and work outward
in concentric circles. Fit the first piece of glass in
the corner. Gently tap the glass into position with a
soft hammer or small piece of wood and a regular hammer.
The blade of your lead knife can be used to raise the
glass into the lower leaf of the channel. Correctly
positioned, the glass should line up with the lines of
your work drawing. If not, grind or groze accordingly.
Use horseshoe nails and a piece of scrap lead to hold
your pieces of glass in place as you work.
- Step 4. Each strip of lead must
be measured, marked, cut, and mitered to fit flush
against intersecting leads as you continue your project.
To do this, you can leave the glass in place or remove it
and hold it in your hand. Measure the length of the glass
and cut the lead slightly shorter. The exact amount
shorter depends on the size of the leaf of the lead which
you are using. If you are using 1/4" H lead the face
would be 1/4" wide. The leaf would be slightly less
than half the face, or slightly less than 1/8". So,
you will cut the lead slightly less than 1/8"
shorter on both ends so that it doesn't interfere with
any of the leads against which it butts. If you cut the
lead too short, you will have a gap to fill in with
solder later. It's better to cut new lead than to use
HOW TO CUT LEAD CAME
Gently rock your lead knife. Don't press
down too hard or you will crush the heart of the lead. Make sure
that your knife is kept sharp.
If you are removing the glass and holding
it in your hand to cut it, you can also use lead cutting pliers.
- Step 5. Continue positioning
the glass, securing it with nails, and measuring and
cutting the lead came until all of the inside pieces have
- Step 6. Trim the first two
perimeter leads to their correct length.
- Step 7. Square up the panel
with two additional lath strips. You are now ready to
- Step 8. First make sure that
all of your joints are clean. A small wire brush or fine
steel wool will clean off any oxidation and insure a good
strong solder bond.
- Step 9. Apply flux to each of
- Step 10. Holding the end of the
solder on the joint, touch the tip of the iron to it. A
small blob of solder is sufficient to bond the joint. Be
careful not to hold the iron on the joint too long
because you will melt the lead.
- Step 11. Turn the panel over to
solder the other side.
HOW TO TURN A PANEL
When all of the joints on the first side of
the panel are soldered, the piece must carefully be turned over
so that the other side can be soldered. Great care must be taken
in doing this so that it does not come apart while you are
turning it over.
At this point in the work, a panel is at
its weakest -- it must be supported as much as possible. When
turning large panels, sandwich them between plywood.
After removing the lath strips, carefully
slide the panel toward you with its longest side parallel to the
table edge. Slide the panel until it is slightly more than half
off the table. At this point the panel will begin to tilt.
Firmly grasp the bottom edge of the panel
with one hand while holding the top edge with your other hand.
While sliding the panel toward you, you will be lowering the
bottom edge and raising the top edge, using the edge of your work
table for support. Once you have the panel off the table, it will
be in a vertical position.
Now put the bottom edge of the panel on the
table surface slightly less than half the width of panel away
from the table edge. Rapidly lay the panel down, taking care that
your fingers do not end up between the panel and the table
surface. Slide the panel back onto the table surface.
- Step 12. Solder the other side
of the panel.
After you have completely soldered all of
the joints on both sides of the panel you should (if the piece is
larger than a small decorative suncatcher) cement the lead came.
The process of cementing waterproofs and strengthens the piece.
Use a ready-to-use cement specifically designed for stained glass use.
- Step 1. Force the cement under
the leaves of the lead with a natural bristle brush.
- Step 2. If you have used flat
came, gently flatten the leaves of the lead with your
lathkin. This will force the excess putty out of the
- Step 3. Remove the excess
cement with a sharpened dowel.
- Step 4. Liberally sprinkle
whiting, or fine sawdust over the
piece. Scrub with a clean, dry natural bristle brush.
This procedure will polish your glass and clean away any
grease and dirt.
- Step 5. Repeat steps 1-4 on the
other side of your project.
Allow your piece to dry flat
for at least 24 hours.
to "The Copper Foil Technique"