In Brief.

Rotary hammer drills are generally used for masonry drilling & occasional light demolition & renovation work. They are also referred to as ‘roto’ hammer drills or masonry drills & are very popular with pest controllers for drilling holes into concrete slabs.

A rotary hammer drill draws its name from the two different mechanical actions it uses - rotary (drilling) & hammer (chiselling). The most important function of these machines is the ability to engage rotation & hammering at the same time! This creates a very powerful drilling force capable of drilling through solid masses of concrete & masonry.

In some drills the hammer action can not be disengaged to enable regular drilling. As these drills are specifically designed for working with concrete, you may need to consider whether the ability to drill other materials is important or not.

When it comes to chiselling, many drills provide a neutral position on the mode selection switch. This feature enables the chisel to be rotated to the angle of ‘best-fit’ before selecting the hammer mode.

The hammering speed of the reviewed drills ranges from around 2700 to 5800 BPM (blows per minute). Each impact, punch or blow carries a certain amount of force behind it, which is measured in ‘Joules per impact’. The rate of Joules delivered ranges from 2.2 - 5.5, with the larger figure being the more powerful.

Due to the nature of the work performed by these drills, it is essential they have an extremely sturdy chuck. The chuck style used with a rotary hammer drill is called the Special Direct System or SDS. The drills in this review use the SDS-Plus bit fitting system whilst even larger machines use the SDS-Max system. SDS-Plus & Max drill & chisel bits are specially designed with grooves & indentations which align with the locking mechanism within their respective SDS chuck.

What we Did.

We divided the drills in this review into two categories based on the maximum width of the drill bit specified by the manufacturer. The first category includes those with a capacity ranging from 22 - 26mm; the second category is sized from 30-36mm.

Keep in mind that the shank on an SDS-Plus bit is 10mm in width & the flute of the bit is wider or narrower, depending on its sizing. So, although it is physically possible to fit a bit that is higher than the specified size, we advise against you doing this!

We used a 12mm SDS-Plus masonry bit to drill a line of holes through an 80mm thick slab of steel reinforced concrete. We timed our operator as he drilled each hole to gain a general indication of each machines drilling speed.

We then fitted a chisel bit & selected the hammer only action to break up the concrete between the line of drilled holes.

What We Found.

All of the machines drilled through the concrete slab quickly & with ease. An industry expert stated that 95% of the time these drills would be used for hammer drilling through masonry, rather than be used to perform major chiselling work.

Although some of the drills reviewed would be very capable of chiselling floor tiles & breaking up concrete, if you were in the demolition trade you would use a larger machine that would allow the drilling to be done from a more comfortable standing position.

All the machines reviewed supplied an equally solid SDS chuck made of high quality & hard wearing materials.

All machines 22-26mm come with a trigger lock & reverse drilling. These features are not available on any of the larger machines reviewed.

A 13mm keyed chuck with an SDS-Plus shank, is an optional accessory that can be used to convert these drills to a regular drill (which means you can use all your regular drill bits). In this case having a reverse action is essential for removing stuck bits when drilling through timber.

In the 22-26mm category, the Makita HR2470 delivered an outstanding masonry drilling speed! In fact, its drilling rate exceeded some of the drills in the 30-36mm category.

In the larger drill category, the Hitachi DH30PC2 was the stand-out performer. With a drilling rate 30% faster than its competition we were very impressed!

The large GMC RHD1500 deserves a mention for its incredible pricing. At 1/6th of the cost of its rivals it offers extremely good value for money.