About Mortise Chisels

A mortise chisel is the heaviest of all chisels and made for cutting. It has many uses, including making a space for the plunger on a lock in your doorframe. The term mortise is because you use the chisel to chop out joints. These are mortise and tenon joints where the tenon is a protrusion that fits into the mortise, the hole with a similar shape, to interlock and create the joint.

History

Use the mortise chisel when you want to remove wood from an area. Many of the joints in furniture built in the 1700's contained the mortise joint because it was so strong. Sheraton desks and Philadelphia Chippendale Highboy's from that era contain mortise joints. The tool was one of the first hand tools used by craftsmen. Today it has a place in the toolbox of not only the crafter but also every carpenter or handyman.

Features

Recognize the heaviness of the blade and handle. These have to be strong enough to take a whack from a mallet. Most of the handles on mortise chisels have reinforcements, despite the fact that they are hardwood like ash or beech. The metal hoop at the end of the chisel prevents the wood from splitting when you hit it with a hammer. There's another ring at the base of the wood on most mortise chisels called a ferrule, which stops the handle from splitting at the base when you strike it. The steel blade has a 28 degree angled bevel, with the secondary bevel at around 35 to 40 degrees.

Size

Purchase several different sizes. The mortise chisel is nothing more than a specific width piece of steel with the end beveled. If you use hand tools often, it's wise to purchase several different sizes of mortise chisels. They come in sizes that range from 1/16-inch to 1 1/4-inch. The most commonly used are the 1/4-inch and 3/8-inch mortise chisel.

Considerations

Check out the sash mortise chisel. Sash mortise chisels are lighter weight and used primarily for the more shallow mortises found in windows. Use these if you pre-drilled out the mortise and you should have no problem with the weight and durability of this type of mortise chisel.

Prevention/Solution

Choose a swan neck mortise chisel if you want good leverage in deep areas like lock installations. Use the wall of the mortise to make the curve in the blade a fulcrum so you clean and true the bottom of deep mortises

Effects

Select a longer mortise chisel to save your effort for other projects. If the mortise chisel is long and heavy, it's easier to hold plumb and gives more stability when you whack it with the mallet. No matter what type you select remember to keep it sharp, that's the key to a good cut.

Identification

Investigate the mortise chisel and bit for power tools. This square exterior of the mortise chisel, known as the hollow mortise chisel, combines with a drill bit on the interior of the square. The drill bit on inside precuts and clears the area and then the mortise chisel cleans up the lines on the outside so its straight.