Hammer Drills

A variation on the standard power drill is the hammer action drill. Fitted with either a keyed or keyless chuck, these powerful drills often have a variable speed setting and a reverse gear – handy for removing screws! Falling into several sub categories, they are designed with a twin action facility. Firstly, they rotate like a standard drill, making them useful for woodwork and secondly, they have a hammer action, making penetration into tough material easier. By far the most powerful of this range of drills is the super-powerful pneumatic SDS design.

Choosing Hammer Drills

When buying a power drill, it is important to pick the right model. Hammer drills on World of Power can range in price from an entry-level £50 to over £700 for the professional SDS models. If you are using a standard hammer drill for occasional DIY then you won't be needing half the features that come fitted as standard on the higher range models. However, due to the power of these drills, a safety clutch is an important feature to look for, especially when drilling masonry. This highly practical device eliminates the possibility of the bit jamming and causing serious injury.

SDS Hammer Drills

Introduced several years ago by manufacturers Bosch, the SDS system has revolutionised the ease with which a drill can penetrate hard masonry. This system features a super-enhanced hammer action, which delivers hundreds of times more energy per hammer blow than conventional hammer drills.

Combine this with a chuck and drill bits specially designed to effectively eliminate the possibility of bit slip and to withstand the force of an enhanced hammer action and you’re talking about a drill which can punch a hole through anything!

Hammer Operating Modes

SDS drills have three modes of operation:

• Drill only
  Like a standard drill - maximum speed however, tend to be slower than usual (under 1500 RPM) and torque higher.
• Drill and hammer
  Combined hammer and drill action. Despite the fact that SDS drills are far more powerful than standard hammer drills they tend to be quieter.
• Hammer only (No rotation)
  This function is not available is some models and is sometimes referred to as an SDS+ drill. This function greatly expands the range of tasks you can carry out with your drill. With the use of a SDS chisel bit, you can use the drill like a mini Kango or concrete breaker. This is ideal for chasing cable runs or cutting out sockets in walls and light demolition work.

Hammer Drill Top Tips

Like we've previously touched on, if your work does not go further than light DIY, then a basic drill will more than suffice.

If you're thinking of working with hard masonry or concrete on a regular basis, then you must consider investing in a mid to high-level drill for safety reasons alone.

Many of the budget drills are heavy. This is fine for light demolition but not so good for prolonged work so you need to bear this in mind.

Some budget drills will need frequent lubrication with grease and after a while – but this will begin to make an unwanted appearance from various places within the drill. This can be a pain as it can and does get splattered about, which is no good when you’re working in a clean environment, so make sure you lubricate the correct measurements and prepare your work area properly.

A chisel position lock is also useful when using your drill in hammer mode. Many budget drills disengage the rotation of the bit but leave it free to turn, making chiselling a straight chase in a wall near impossible. Look for a model with a position lock if your work will involve a lot of chase work.