Wood chisels are used for cutting and paring timber. They consist of a steel blade with an extremely sharp cutting edge and a handle. Chisel handles used to be made of wood, but today they are more commonly made from shatterproof and impact-resistant materials, such as cellulose acetate. This is necessary, as the handle has to withstand being hit countless times during the chisel’s lifetime. If the handle of a chisel cracks or splits it should be thrown away immediately.
There is a wide range of chisels available but for most DIY projects the four listed below in a selection of blade widths should be sufficient.
Mortise chisel
Used generally for cutting deep mortise joints, the mortise chisel has a thick blade for greater strength and will look square rather than rectangular when viewed in profile.
Firmer chisel
The firmer chisel is similar to the mortise chisel in appearance but its blade will not be as thick. Therefore the cross-section of the blade will be rectangular. This is a strong chisel designed to carry out heavy-duty work.
Bevel-edged chisel
A versatile chisel that makes very accurate cuts and consequently it is used in the cutting of many different types of joints. The bevel-edged chisel has one side completely flat but the reverse side has tapered edges.
Paring chisel
The paring chisel is similar to the bevel-edged chisel but with a longer blade. Paring is the measured removal of small shavings of wood. This can be done with most chisels but the long blade of the paring chisel makes it easier to control.
Sharpening wood chisels
For a chisel to continue working effectively the blade must be kept sharp. This is carried out using a sharpening stone, the most common being made of silicone carbide. Different grades of sharpening stone may be needed, with a coarse stone required for removing larger pieces of metal when the blade is chipped and a smoother stone for achieving the final cutting edge.
- To sharpen a chisel, moisten the stone with oil or water.
- Then place the tip of the blade on the stone using the bevel of the blade to get the correct angle.
- Move the angled blade backwards and forwards repeatedly to sharpen the cutting edge.
- When you are satisfied the blade is sharp, turn it over and place it flat to the stone.
- Moving the blade backwards and forwards while it is in this position will remove any burrs from the cutting edge.
Chisels are often supplied with plastic caps or covers to protect the cutting edge, so always fit them when you are storing your chisels.