How Does A Hammer Drill Work: Science Behind

An effective tool used mostly for drilling through hard materials is a hammer drill, sometimes referred to as a percussion drill. Let us view the hammer drill in action.

The following is a list of how a hammer drill operates:

  • Make a surface mark
  • Install the drill bit
  • Define the depth
  • Begin drilling
  • Tidy up the hole

Make a surface mark

Making sure specialists have marked the wall or surface on which they desire to drill with a pencil and a ruler is the first step in using a hammer drill.

Install the drill bit

Before fitting the drill bit, be sure to put on protective goggles to prevent any dust from going into the technician’s eyes. To expand the size of the hole, a technician should always drill a small hole initially with a smaller drill bit, then switch to a larger bit and drill once more.

Define the depth

Although some hammer drills won’t have a depth stop, if the technician has one, be careful to set the depth to the proper level. Otherwise, technicians can use some masking tape.

Begin drilling

Some hammers start slowly and utilize the least powerful setting to make the guide hole. The technician can then start gradually increasing the speed and power. If more is needed, the technician can raise this even further.

Tidy up the hole

Make sure the technician maintains interrupting the drill every 15 seconds to remove the bit and clear the hole of dust. Once the technician is done, he or she can blast any leftover debris out of the hole with compressed air.

Rotating drills with an impact mechanism that produces a hammering motion are known as “hammer drills.” We will go through the rotary hammer drill’s operation and the hammer drill diagram in more detail.

Hammer drill diagram

The body of a hammer drill resembles that of a power drill or an effect driver, but a kit is not ideal for masonry. Let us check out the diagram for the hammer drill.

Image Credit – Bohrmaschine by Honina (CC- BY – SA – 3.0)

How does a rotary hammer drill work?

A very little amount of weight and length is added by a hammer drill together with a mechanism that gives the drill a chipping motion during drilling. Let us watch how a rotary hammer drill works.

  • The drive piston in a cylinder is moved back and forth by an electric motor turning a crank. The opposite end of the same cylinder houses the flying piston. The air pressure in the EP cylinder, as opposed to the springs in cam-action hammer drills, enables a considerably more efficient transmission of pounding energy, despite the fact that the pistons do not actually touch.
  • This EP technology is used by the majority of contemporary rotary hammers, as well as by all electric-powered chipping or jack hammers. The hammer and rotation functions can now be utilized singly, in tandem, or both, i.e. in hammer mode, drill mode, or both.
  • When in hammer mode, the device works as a jackhammer would when drilling. The oil-filled gearbox of rotary hammer drills permits them to function durably despite the strong forces, shocks, and grit-filled conditions in which they are frequently utilised.
  • They need a “slip clutch” because of the type of work they do, which activates when the drill bit jams and enough torque is applied to the “slip clutch” mechanism. This prevents the damaging violent yanking motion that a drill without a clutch would make when stopped abruptly from full speed.
  • While the slip clutch safeguards the operator, accidents can still happen. A few manufacturers have added more technology to safeguard the operator. When the tool body starts rotating excessively, Hilti’s “ATC” or “Active Torque Control” technology disengages the drive from the motor by acting on a secondary magnetic clutch in addition to the conventional slip clutch.
  • DeWALT has a similar technology known as “Complete Torque Control” (CTC), which makes use of a two-position slip clutch and allows the user to choose the lower torque level for increased safety.
  • Different manufacturers have created numerous “unique shanks.” Many of these proprietary methods have changed over the years, but the three shanks still in use today are SDS+, SDS-MAX, and SPLINE SHANK.
  • These shanks were created so that the drill bit could effectively transmit the force of the electro-pneumatic hammering mechanism to the work surface by allowing the bit to “slide” back and forth while revolving.


Pick a bit with specialized carbide tips made to endure hammer drill impact. Select either the Masonry Carbide Tipped SDS PLUS Drill Bits or the Masonry Carbide Tipped SDS MAX Drill Bits for superior cut quality in concrete.

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