Here on the gulf coast a hammer drill is of little use for drilling into a concrete slab because the rock used in the concrete is very, very hard just as it is in many parts of the country.
A hammer drill works with a larger number of blows per minute but it does not hit hard enough to break thru the rock used along the gulf coast. It will however work fine in a brick or cinder block wall.
A rotary hammer hits slower but with an impact force 2 to 3 times over a hammer drill.
One way to know the difference is a hammer drill has a 3 jaw Chuck where a rotary hammer has either a Spline drive or a sds-plus or a sds-max depending on the capacity and many rotary hammers have a three mode operation. Hammer mode for drilling in concrete, a rotation only mode for drilling in wood and a chipping mode for chipping concrete or removing tile and thinset mortar.
A hammer drill has two “hammer dogs” that mechanically “rub” together to make its impact. Rotary hammers use pneumatic pistons to generate their impact energy, and don’t have metal-on-metal wear and tear.
Bosch is our preferred line of Rotary Hammers the Bosch 11255 VSR is a great hammer for holes up to 1″ as well as removing tiles and light concrete chipping.
The rotary hammer will outlast even the best hammer drill and the bits have a better grade of carbide for serious concrete work.Read More