Modern hammer drills today typically use the SDS system of drill bit attachment developed by Bosch and Hilti in 1975. Other hammer drill bit systems do exist but the SDS system seems to have taken hold with tradesmen and DIY-ers alike leading to it becoming the dominant type the world over. Today, three different SDS formats exist that are non-interchangeable, SDS-Plus, SDS-Max and SDS-Top. SDS Plus accepts a 10mm diameter shank (the part of the drill bit that attaches to the chuck) and is the most common type of SDS used. Designed for hammer drills up to 4kg, it is capable of handling the majority of building work needs and so has become the most common type. The SDS-Max system uses an 18mm diameter shank and is designed for larger hammer drills (5kg and more) and for more aggressive drilling. The SDS-Top specification whose characteristics partially overlap those of both SDS-Plus and SDS-Max drills is not very common and is slowly fading from use. In fact, you would be hard-pressed to find an SDS-Top-specification drill for sale in today’s market so we will ignore it in this review. Furthermore, we are pretty much going to be focusing here on SDS-Plus drills only since they are the dominant type of impact drills on the market today and, in reality, unless you need the extra high drilling power for a specific job that an SDS-Max drill affords, you are typically going to be buying an SDS-Plus hammer drill.
What to look for in an SDS-Hammer Drill
Cheap Muscle vs Refined Quality
In the table below you will find some of the most popular SDS-Plus hammer drills available in the UK at the present time. In general, SDS-Plus hammer drills fall into two broad categories, the less well-known, less expensive, fewer ‘bells & whistles’, and heavier drills (the Wolf, Silverline, and the Terratek), and the brand-name, more expensive, more universal, better-made, and lighter hammer drills of Bosch, Makita and other well-known power tool manufacturers. So one of the first decisions to be made when purchasing a new hammer drill is to first decide on which of the two categories is more important to your purchasing decision.
The maximum revolutions per minute or RPMs that a drill can accomplish will be mainly determined by what sort of work the drill was designed for. Lower speeds are used to penetrate harder materials such as masonry, while higher speeds are used for softer materials like timber. As a result, many of the drills designed exclusively for masonry work will have lower overall maximum speeds, while more multi-purpose hammer drills that can also be used to drill timber and metalwork will have higher overall speeds usually with some form of speed control integrated into the design.
Blows Per Minute (BPM) and Impact Energy
These are important parameters for hammer drills as they determine how easily masonry is drilled and chiseled. The higher the BPMs and the higher the impact energy or each blow, the easier it will be for the drill to make its way through the masonry. If the drill has an easier time going through the material, it means the drilling will be smoother and more accurate.
Weight of the drill is an important characteristic for hand drills. If you are going to be working with the hammer drill above shoulder level or for extended periods of time, then having a very heavy drill will become inconvenient in a hurry. Even some of the lighter-weight hammer drills (2-3 kg) can become bothersome when used in an elevated position, so you can just imagine what working with a 6kg drill will feel like (that’s assuming that you are of sufficient physical stature to manipulate the drill in the first place!)
SDS hammer drills also tend to come with some common features too, such as multiple modes of operation. These days almost all hammer drills have the ability to switch off the rotary or the hammer action of the drill, usually providing the user with three modes of operation:
- Rotary action only (for drilling into wood, metal and plastics)
- Rotary hammer action (for hammer drilling into masonry, concrete and other hard materials)
- Hammer action only (for use as a power chisel)
Another common feature of hammer drills comes in the form of their safety characteristics. In the interests of user safety, and since today’s hammer drills generate such high levels of torque, SDS hammer drills almost always include a slip-clutch or torque limiter to prevent loss of control of the drill and potential user injury in the event of drill bit binding. The slip-clutch or torque limiter ‘detaches’ the rotary action of the drill bit from the drill motor if the drill bit jams in the substrate while drilling and thus prevents the whole drill rotating around the stuck drill bit potentially injuring the operator.
Most Popular SDS Hammer Drills in the UK
|SDS Hammer Drill||Max Speed (rpm)||Blows Per Minute||Impact Energy (Joules)||Motor Power (W)||Weight (kg)|
|**information not public|
|Bosch PBH 2100 RE||2300||5800||1.7||550||2.2|
Wolf 1500W SDS
The Wolf hammer drill is more about power than it is about refined drilling. Due to its heaviness and power, this is the drill recommended more for heavier demolition work than it is for accurate masonry drilling. Like other powerful hammer drills, it has a slip clutch – an important safety feature for both the operator and the drill itself – to prevent the drill from spinning out of control if the drill bit jams. It also has a much needed rear dampener on the handle that reduces vibration stress on the user. In addition to its hammer drill action (drill bit rotation and hammering) the Wolf drill can also be used as a regular drill if need be by selecting the rotary only function, and it can also act as a power chisel with hammer action only. However, as there is no drilling speed control, the machine can be a bit too powerful for some lighter drilling applications, and hole position accuracy can suffer. Wolf-branded products are primarily sold by the UK Home Shopping network and tend to be good value products where you want a decent power tool that does the job but without the high price tag of brand-name tools. However, take note that this is a very heavy drill at 6kg and is tiresome to hold for any length of time. In fact, it is the weight and power of the 1500W motor, that allows this beast of a drill to drill through almost anything with ease. One thing that is missing from the drill is a reverse setting which can be used to get out of situations where drill bits become jammed, but for the price at which this drill is available, you really can’t expect it to do everything and then some!
Silverline 633821 SDS+
The Silverline 633821 hammer drill is another decent piece of kit in the Silverline power tools inventory but professionals beware as it is not really a tradesman’s tool and any excessive use in any one sitting, will overwork the drill and it won’t like it. But given its relatively small price, it is definitely worth the money for small DIY jobs. It can drill up to 26mm diameter holes in masonry without any problem and as with other modern hammer drills, it can also be used as a rotary only drill or as a power chisel. Unlike the the similar-looking hammer drill made by Wolf, this Silverline one comes with a reverse drill setting that can be used to get the drill out of sticky (drill bit) situations. In addition, it also provides rudimentary drill speed selection making it an overall more universal drill for both lighter as well as heavier jobs.
Bosch PBH 2100 RE SDS+
The Bosch PBH 2100 RE has a less powerful motor than some of the other hammer drills discussed here. That’s because the drill tends to be more of a universal drill rather than just a hardcore hammer drill – it even has a setting for screwdriving! – but make no mistake, the Bosch PBH 2100 RE is still a very respectable SDS-Plus hammer drill as well. The maximum hole diameter that it can produce in masonry is 20mm, a more modest value than for a specialised hammer drill but still more than what most builders and home users will ever need. To get the Bosch PBH 2100 RE to use regular bits or to act as a screwdriver, chuck adaptors are available for purchase separately that take non-SDS and screwdriver bits, respectively (see images below). Both chuck adaptors work by simply slotting directly into the SDS-Plus chuck with the drill having a selector for reversing spindle rotation, an important feature for getting drill bits out of jams in addition to changing screwdriving directions. As with a standard hammer drill, the Bosch PBH 2100 RE can also switch off its rotary motion while preserving its hammering capabilities so it can also act as a light power chisel. Unlike some of the cheaper hammer drills available, the Bosch PBH 2100 RE has rotational speed control incorporated into the trigger, so that increasing the pressure on the trigger slowly increases the speed of the drill or screwdriver bit rotation. The drill is also relatively light in weight, which is not a bad thing if you need to work with it up a ladder or above shoulder height. In fact, some of the heavier hammer drills available are near impossible to use effectively for work higher up. Finally with the Bosch brand, you can rest assured that you are buying a quality drill, a tool that is very well made and built to last a very long time.
Terratek 1500W SDS+
The Terratek 1500W is the main competitor to the powerful Wolf hammer drill. It has essentially the same high power of the Wolf but with only two thirds of its weight. It even incorporates a similar vibration dampener as the Wolf within its handle to reduce impact stress on the operator. Like other drills in this category the Terratek hammer drill uses SDS plus drill bits. Unlike other competitors, the Terratek also includes a keyed chuck adaptor that can be slotted into the standard SDS chuck and allows you to use your traditional hammer drill bits – useful if you have been a long-time user of hammer drills and have built up your inventory of standard masonry bits. As with other SDS hammer drills, the drill has a safety clutch to ensure that if the drill bit jams while being operated, the drill won’t rotate violently out of control injuring the user. The Terratek hammer drill also features a reverse setting to deal with bit jams and similar situations, and as with many other of today’s hammer drills, can also be used as an power chisel by disabling the rotary action while keeping the hammering function. Similarly, you also have the option of using the Terratek drill as a regular drill by switching to the ‘rotary only’ setting but at an intrinsic weight of 4kg, it is not meant to replace your ‘everyday’ drill.
Makita HR2610 SDS+ (our favourite)
With the Makita HR2610, you pay a higher price but you have the comfort of knowing you are getting a quality Japanese product. It has all the standard settings of a typical rotary hammer drill, allowing the user to also use it as a regular drill (rotary-only setting) as well as a power chisel (hammering-only setting). It can drill holes up to 26mm in masonry. For safety of the operator and the drill itself, it has a torque limiting clutch to prevent loss of control of the drill if the drill bit jams while drilling. In addition, the drill also has a reverse setting for drill bit-jamming situations. Quality on the Makita is second to none and as expected this is reflected in the price compared to some of the cheaper hammer drills available that are less well-built. The trigger has variable speed control through the amount of pressure applied to it giving the drill more controllable and more accurate drilling capabilities. Makita power tools tend to be up there with the most expensive brands, but as the old adage goes: ‘you get what you pay for’ and this happens to be particularly true with Makita. Makita power tools are precision tools, that include all the latest technology and are built to last.