Cutting Lead & Stretching Lead

Cutting lead, like cutting glass, has several different techniques using different tools. This tutorial will show you how to use those tools when it’s time to start leading up your window.

However, before I show you about cutting lead, I want to show you how to stretch lead. This is something you may occasionally have to do in order to straighten the lead or to put a “set’ in it.


How To Stretch Lead

There is a big controversy between those that stretch lead and those that don’t. I’m somewhere in between. If the lead is very soft and “floppy”, I stretch it to give it some body or stiffness or rigidity, what ever you want to call it. Cutting lead is much easier if the lead has some stiffness to it. If the lead is already fairly stiff, I leave it alone. The only other time I stretch lead is if it has been slightly twisted. There is only so much twisting that can happen before the lead can not be straightened out at all.

Most lead is now made with the addition of a small amount of another metal, such as antimony, tin or copper which makes it much more rigid than the lead of years ago. Therefore, there is less, if any, need to stretch it.

If you have the need to stretch your lead, here are several ways to do it.

Have another person help you. Each one of you will hold an end of the lead with pliers that have teeth/ridges in the jaws. Even breaking pliers will work as long as they have teeth. Make sure you are holding the lead tight. Really squeeze the jaws. One person holds still and the other gently pulls until you feel the lead “set up”.

By gently pull, I mean don’t yank on it, just pull slowly and steadily. It does take some strength to stretch lead. You’ll be pulling hard enough that if the lead should break you’ll lose your balance and fall backwards. One way to help prevent falling is to stand with one foot planted firmly on the floor behind you, or stand with a table or door close behind you.

I would imagine that almost everyone that has ever stretched lead has had this mishap. Until you have experienced it, you have no idea what it’s like to be pulling hard on something as it breaks. There is no time to think about staying upright.

When the lead “sets”, you will actually feel the difference. It will be stretching fairly easily, then all of a sudden it becomes much more difficult to pull on it. When that happens, stop pulling. If you pull too hard or more than the “set”, the lead can, and probably will, break.

Stanton Lead Stretcher
If you are going to be working with lead frequently, buy a lead stretcher. The one I recommend, is the Stanton Lead Stretcher. It will stretch your lead a maximum of 8 1/2 inches. It uses the simple principle of leverage and makes the job of stretching lead very easy and safe.


Another stretcher is the Lead Vise. It screws on to your work bench. One end of the lead goes in the lead vise. The jaw clamps down and the harder you pull the tighter the jaw gets. You should only pull until you feel the lead “set”. If you pull it any more, there is a danger of the lead breaking and you taking a tumble. Use the same safety precautions as described above for two people using pliers.

How do I know about falling backwards when lead breaks?? All I can say is that I’m lucky that I landed wedged between a box of glass and a work bench rather than in the box of glass. For some unknown reason, I had a false sense of security, and thought it could never happen to me. I was in a hurry, didn’t think, and down I went. So, beware…it can happen to anyone, from a newbie to an experienced glass worker.

That’s it for stretching lead. If you have questions or comments, please feel free to Contact me.

Are you having problems with a technique or any other area of your stained glass work? If you are, click here to tell me about the problem. You should have an answer within 2 weeks.

Can’t find what you’re looking for? Use this search box to search the world wide web.

Cutting Lead With a Lead Knife

On the Lead Came page I showed you all of the tools needed to construct a window using lead. Look at the pictures of Lead Dykes and Lead Knives. Those are the main tools you will need for cutting lead. In addition you’ll need a Fid and a retractable, fixed blade or snap off knife to mark the lead where you want to cut it. Also, a block of wax or paraffin will come in handy.

For a lead knife, I have always used a putty knife with a sharpened blade, and that is what I am using in the picture that follow. The technique is the same, for cutting lead, no matter what you use for a lead knife.

When you are cutting lead with a lead knife, you start the cut on the face/top of the lead, not the channel. Firmly rock and wiggle the knife from side to side as you are pushing the knife through the lead. Don’t push so hard that you twist or crush the lead. There is a fine line between pushing firmly and pushing too hard! Practice will teach you how hard to push. You need to be holding the lead steady with your other hand, as indicated in the picture. If the knife is difficult to get through the lead, it is probably dull.

You can sharpen the lead knife on an oil stone; however, before you do that, run the knife through a block of wax or paraffin and see if that makes a difference. The wax or paraffin often lubricates the knife enough to make it go through the lead quite easily. An oil stone is an abrasive stone used to sharpen cutting tools. Here’s a place where you can find out more about oils stones (referred to as sharpening stones in the article): Oil/Sharpening Stones. Under “Science and Technology Dictionary” click on “more articles below”.



Cutting Lead With Dykes

You will notice that the blades of the dykes have a flat side and a V shaped side. The flat side will give you a flat cut and the V shaped side will give you a V cut, with the V sticking out. When you use your dykes, the most important thing to remember (and do) is to always have the flat side towards the piece you want to keep. When you are cutting lead into shorter pieces from a long piece of lead, you will need to trim off that V before you do each cut. Yes, there will be a small amount of wastage, but those cut off V’s can be used when you are constructing your panel. You will see how they are used when we get to constructing a panel.

When you are cutting lead with dykes, you have the dyke blades across the channels, not the faces of the lead. Maybe an easier description would be…cutting the lead side to side, not top to bottom as you do with a lead knife. Once again, remember to keep the flat side of the blades against the end of the lead that you want to keep.

Cutting lead at an angle with lead dykes:

Mark the lead where you want to cut it.
Cut just the top face off. You won’t be able
to hold the dykes straight up and down to do this.
You will be holding them at a tilt.

The top face is now cut at an angle.
It will be used as a guide for cutting the bottom face.

Cut the bottom face by using the, already cut, top face as a guide. Trim the angle if it needs it.

Here is how the finished angle will look.

Cutting wide lead with dykes:

This is how to cut wide lead with dykes. It is basically the same as cutting lead at an angle. You cut the top face first, then the bottom face.If the lead is wider than the dyke blades, cut one half of the top face, then cut the other half. Do the same with the bottom face. An alternative is to cut the top face as described, then bend the bottom face downward. Sometimes it will break off at the bend. If it doesn’t break, you will at least have a creased line to cut along.

This is how the wide lead looks when it has been cut with dykes.

Opening the channel with a fid:

Occasionally, you will need to open/widen the channel of the lead. The glass may be too thick to fit in or the lead may have become squeezed closed a little while cutting it. For whatever reason, you will need to open it. This is one of the places you will use your fid. Insert the fid at one end of the lead channel and pull it along until you get to the other end. You can also use the fid to straighten up points on angle cuts. The points quite often get pushed down during the cutting process, especially when you are cutting lead with a lead knife.

For the tutorial on making a leaded window click here:
Making A Leaded Window

For the tutorial on soldering a leaded window, click here:
Soldering A Leaded Window

For the tutorial on how to putty a leaded window, click here:
Putty A Leaded Window

For the tutorial on how to lead up a circle, click here:
Leading Up A Circle

For the tutorial on how to lead up a diamond, click here:
Lead Up A Diamond

Scroll to Top
Available for Amazon Prime