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.

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 (*).

• 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 too-short pieces.

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 been fitted.
• 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 solder.
• 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 the joints.
• 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 leaves.
• 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.

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