A rotary hammer is a rotary drill with a hammering action designed to punch holes in hard surfaces. They are also called combi drills. Rotary hammer uses a piston mechanism to pound the drill bit in and out while spinning. The piston rides in a cylinder and creates air pressure when driven forward, and it’s air pressure that actually drives the hammer mechanism. This makes them deliver a powerful hammer blow, making it possible to drill bigger holes much faster. They excel at drilling holes in hardened concrete. They are much more durable and are the preferred tool of the pros.
When you buy a rotary hammer it is important to decide on what features matter to you. The main considerations are how much power you require, the size and weight of the tool, whether it should be cordless and how often will you be using it. The power plays a major role in deciding the capabilities of rotary hammer. They come in power ranging from 450 to 2000 watts. Tools with power up to 900 watts are the household rotary hammers and tools with power more than 900 watts are the professional ones.