What is a Morse taper?

A Morse Taper is a long standing standard which is used in the manufacture of taper shank drills. The tapered shank is used to secure the drill to the spindle of a drill press. As the spindle of the drill press rotates, the bit is held in place through friction between the surfaces of the tapered shank and the hollow spindle. These drills are used in manufacturing industries as they allow for rapid tool change from one diameter drill to another.

The Morse Taper is but one of the many families of taper bits but it is the most popular and prevalent. The taper itself is approximately 1.5 cm per 30.4 cm, or about 5/8” per foot. The sizes are designated by number; there are eight sizes as standard, from number 0 to number 7. The most common size is 2. The smaller the number the smaller in diameter the parts are.

Morse taper shank drills have a tang at the end; this tang fits into a corresponding slot deep in the spindle of the drill press. The taper is that which holds the drill bit in position using friction. These bits are ideal for light pressure drilling as the friction is enough to hold the bit in position. If heavy pressure is exerted, the bit will often spin freely in the spindle instead of drilling a hole.

It is the job of the tang on top of the bit to secure the bit into the drill press spindle; the tang fits into the corresponding slot. The tang keeps the bit from losing the friction grip and simply spinning, even when the drilling pressure is increased or the drill runs into high resistance. The machine operator puts the taper into the spindle and then turns the bit until he feels the tang engage. The spindle is brought down onto a piece of material, usually wood to ram it home and secure it tightly. The spindle has a rectangular hole in it and the tang can be accessed through the hole by a wedge shape piece of metal, which, when hit with hammer, loosens the bit and it falls free.

There are a number of accessories available which can be used to increase the bit length or to adapt the bit to fit a different socket.


Pin It on Pinterest