Different Types Of Drill Bit Shanks

The portion of a drill that attaches to the chuck of a rotating mandrel is called the drill bits shank. The part of the bit that does not drill or grind is the male end. Drill bit shanks vary according to the types of drill bits. Although there may be functional differences, the shape of the shank is the main characteristic.

Types Of Drill Bit Shanks

1. BRACE SHANK

A brace shank is a multi-sided shank consisting of a point that tapers into a chuck through angular dispensation. Brace shanks are more accessible to produce than more complex and durable shank forms and sizes; hence they were more common before current machining techniques made it possible. Brace shank torque tolerances are reasonable, although stripping is possible, especially without using a specific chuck.

2. STRAIGHT SHANK

Straight drill bit shanks are similar to brace shanks, except that their tips are not tapered. The cylindrical tip inserts flush into the chuck as an alternative. While some straight shanks have parallel sides, others have slanted sides. Due to their low torque transfer, round shanks can prevent straight shanks from drilling through complex materials.

To accommodate a range of chuck sizes, some drill bits include straight shanks smaller in diameter than the bit itself. You can use straight shanks widely because they don't need special chucks.

Read More: HSS vs Cobalt vs Carbide Drill Bits

3. HEX SHANK

The hexagonal shape of the shank, which resembles a screwdriver bit, gave rise to the moniker "hex shank." Hex shanks can be used in both special drill mandrel chucks and screwdriver bit chucks due to their form. 

The bit can operate with materials that have high resistance, such as solid metals or geological formations. This is because the angled curvature of the shank allows it to handle higher torque transmissions than brace or straight shanks. However, the tilt might also result in decentering, which reduces drilling accuracy.

4. TRIANGLE SHANK

While the triangle drill bit shank is inclined like a hex shank, it only has three angles, unlike the hex's six. It has many of the same advantages as the hex, such as high torque capacities and accurate centering. It can only attach to as many drill chucks as the hex can.

5. SDS SHANK

These shanks are uniquely constructed with a spring load installation feature that permits a worker to manually insert the shank into a chuck. SDS stands for the German idiom "Steck-Dreh-Sitz," or "Insert-Twist-Stay,"; however, the English acronym refers to "Special Direct System." The spring collapses under strain when drilling, allowing the drill to perform masonry or hammering tasks.

The SDS is a relatively new drill shank, having only been manufactured for the first time in 1975. It is also more challenging to make than most other shanks. Additionally, the SDS forgoes adaptability in favor of specialized capabilities and uses a dedicated chuck.

Read More: Best Drill Bits For Metal and Woodworking

6. TAPER SHANKS

The shaft comprises a cylindrical segment that flattens out at one end. The taper drill bit shank limits Morse taper shanks to chucks. Employees must be knowledgeable about Morse taper bits to ensure proper operation. Torque transmission can fluctuate if procedures aren't followed.

This post will help you choose the appropriate type of drill bit shank.