If you’re often working on project involving concrete and masonry, you’re no doubt familiar with tools like hammer drills and rotary hammers. A hammer drill provides just the action you’d expect. It rotates and pounds to create holes in masonry quickly. For bigger jobs, a rotary hammer is usually a better option. It’s a more powerful tool that can drill more holes and drill bigger holes. They also typically have a chisel only option that enables you to perform more tasks.
For contractors, a hammer drill is an impractical tool and the rotary hammer is the more typical option. The rotary hammer comes in a variety of options, however. Specifically, there are specific categories of chucks, also called drives, for different applications. Here are the common chuck categories.
- SDS
This chuck was developed in 1975 by Bosch. SDS stands for the German words for Insert, Twist, Stay. When using an SDS rotary hammer, the shank diameter of the tool and the bit must match that of the chuck. An SDS rotary hammer will feature a 10mm shank with 2 open grooves and 2 closed grooves. When hammering, the bit will move within the chuck.
- SDS Plus
This category features a distinct difference from a regular SDS rotary hammer. While the shank diameter is also 10mm, there are 4 open grooves instead of just two. Even so, the bits for an SDS or SDS-Plus rotary hammer are interchangeable and run up to 1-1/8 inches in diameter.
- SDS Max
This is the bigger and badder rotary hammer option. Shanks are 18mm in diameter, and bits run up to 2-inches. Additionally, an SDS-Max chuck will be found in hammers over 11-pounds, whereas an SDS or SDS-Plus chuck is limited to rotary hammers under 8-pounds. There are also only 3 open grooves on an SDS Max chuck.
- Spline
These are harder to find, but many contractors swear by them. Because of the way its designed, the spline drive is easier to use for high-torque applications. The bits also run up to 2-inches in diameter like an SDS Max chuck.
The size of hole you’ll be drilling and the material you’re working with will determine what type of bit you use, and the size of your hammer.
To find out which rotary hammer is right for your project, contact us at Maxwell Supply in Tulsa.