Lead knives are generally designed to cut lead came and other tough materials such as hardened putty, uPVC, wood and plastic.
The different shapes of lead knife blade are useful for various jobs.
For instance, the rounded edges can be rocked as you cut and the points of the blades can reach into tight corners.
Hacking blades can be hit with a hammer to exert more force for rough cutting.
Came glasswork
Lead came is used for stained glass and leadlights, joining separate pieces of glass, and as a border for glass panels.
Stained glass involves joining pieces of glass which have been painted and then fired in a kiln, making the paint permanent.
Leadlights, or leaded lights, are plain or coloured pieces of glass, joined to create a larger panel.
Creating the patterns of stained glass or leadlights requires the came to be cut at different, precise, lengths and angles; lead knives with curved blades are perfect for this. The curve of the blade can be used to rock the knife as you cut, preventing the came from being crushed and distorted.
The rigid blades of lead knives can also be used to manipulate lead came around corners and curves, to fit the glass pieces. They can pry open old lead came sections on glass panels so they can be repaired or replaced. They can also chip, or scrape, dried cement or putty from finished glass panels.
If the lead knife has a metal inlay on the handle…
The metal inlay at the end of some lead knives is designed to work as a hammer, for lightly knocking in nails or tacks. Specifically, it’s designed to be used to make stained glass windows, or similar glass panels, so you don’t need a separate hammer.
Horseshoe nails are used to hold pieces in place as each section is put together, before it is soldered. This helps the lead hold the shape you want as you work. This hammer end can also be used to tap glass pieces into place and push pieces of lead came into the required shapes.
What types of came can’t lead knives cut?
Although lead is the traditional material for glazing came, it can also be made from zinc, brass or copper. Lead knives are not designed to cut these tougher came sections, so you will need to use a hacksaw or power metal cutter for this.
uPVC windows
Lead knives are often used by glaziers to assist with the removal and installation of uPVC windows. The strength and rigidity of lead knife blades mean they can be used to trim thin sections of uPVC, and neaten uPVC weld lines. They can also be used to cut window beading and seal strips to length.
Lead knives are sometimes used to remove window beading. The blade can be wedged into the seam of the beading, where it is holding the window to the frame, and used to pry off the beading strips. In addition, lead knives can be used to trim weld lines in uPVC, creating a neat, flat, surface.
Because lead knives are sharp and strong hand tools, they can be used to cut tough materials other than lead or uPVC. The specifications of individual lead knives will advise you on what applications they have been designed for. You should not use your knife outside of its specifications as this could damage or break the tool.
Professional stained glass and leadlight makers will reserve their lead knives for just cutting lead. This is to preserve the life of the blade for as long as possible, keeping cuts clean and neat.
Here are some other uses for lead knives:
Removing old putty
The hacking lead knife is perfect for this job. The wide edge at the back of the blade is specifically designed to be hit with a hammer; it can be used to chip away dried putty from window frames, so windows can be removed and/or replaced.
Other types of lead knife can be used for chipping away old putty, depending on the individual specifications of the knife. The points of lead knives can also be used to scrape the last bits of old window putty or cement out small of gaps.
Lead sheet roofing
The thin sheets of lead used for some roofing applications can easily be cut with most lead knives. However, cutting lengths of tough sheet lead will dull blades quickly, so it is more common now for standard utility knives to be used for this job. This is because you can’t replace the blade on lead knives whereas most utility knives use inexpensive, replaceable blades.
Lino and vinyl flooring
These sheets of flooring are fairly tough, but a sharp lead knife could easily slice through them. Lino knives are very similar to lead knives – the main difference is that the sharp edge of the blade is on the concave, rather than the convex, edge.
Lino knives’ pointed tips can pierce the lino then be pulled backwards to cut. Crescent-shaped blades on lead knives can be used in the same way. Other lead knives can cut lino through by applying pressure across the blade edge.
Leather work
Tough pieces of hide or leather can be cut with a lead knife, allowing you to shape pieces for items such as clothing or furniture.