Viewing a single comment thread. View all comments

nalc t1_jcqrhrh wrote

Minor nitpick, it's a rotary hammer, not a hammer drill.

Rotary hammer uses a special sliding bit called a SDS bit that moves back and forth. Only the bit moves. It also has a mode where it can hammer without spinning and use chisel bits for demolition.

Hammer drill uses a normal masonry bit in an adjustable chuck and has a mechanism in it to vibrate the entire chuck back and forth

Rotary hammer is really what you want for anything beyond just doing a couple 1/8" holes. Having both, a rotary hammer can do a 1/2" hole in a granite boulder faster than a hammer drill can do a 5/32" hole in brick.

Both are colloquially called "hammer drills" but you've got to make sure it's actually a rotary hammer and uses a SDS bit.

3