Hammer Drill. Rotary Hammer. SDS Drill. Impact Drill. And even Rotary Hammer Drill! Confused yet? Don’t feel shy about saying, “Yes” because it is confusing. These types of drills are closely related so that the names are often used interchangeably yet they are subtly different. However that may be, these power tools are used to hammer-drill holes in masonry, particularly concrete, but also granite, brick, tile, and even stone.
A Hammer Drill and a Rotary Hammer both do the same thing, it’s how they do it that’s different.
Impact Drill is a less-common name for Hammer Drill. The hodgepodge term Rotary Hammer Drill usually means a Rotary Hammer but it may just as well mean a Hammer Drill – it just depends on who is using the term and the meaning he imparts to it. In our opinion, Rotary Hammer Drill is a name best avoided (unless someone goes and devises an unnecessary mashup of a Rotary Hammer and a Hammer Drill!) but it is becoming increasingly common.
Hammer Drills and Rotary Hammers rotate a drill bit very fast, like a regular electric drill, but in addition they very rapidly drive the bit up and down – rat-a-tat-a-tat! – like a quickfire ‘hammer.’ The combination of rotational drilling and percussive impact pulverizes the material as it bores a hole into it; the former action easing the way for the latter.
A Hammer Drill has two disks with cams facing each other on the same shaft. As one disk spins past the other, the cams thrust against one another, causing the outer disk to rapidly move up and down. This, in turn, imparts a quickfire hammering motion to the chuck. A Rotary Hammer has a crankshaft and a piston that moves inside a cylinder. The crankshaft drives the piston forward and backwards creating sudden bursts of air pressure in the cylinder, and this, in turn, makes the chuck go rat-a-tat-a-tat!
Because of these differences in mechanisms, most Hammer Drills can be set to two modes, rotation and percussion or only rotation, but most Rotary Hammers can be set to three: rotation and percussion, only rotation, or only percussion. This is because in a Hammer Drill it is fundamentally the disks’ rotation that also indirectly bring about the percussion whereas in a Rotary Hammer the internal rotation and percussion mechanisms are independent of one another. Rotary Hammers are much more powerful than Hammer Drills.
An SDS Rotary Hammer or an SDS Hammer Drill, as the case may be, is a specialised type of that drill. SDS is actually a type of quasi-chuck and shank invented by Hilti, and a name very familiar to our site’s visitors, Bosch. SDS bits have a few advantages including superior drilling, greater torque, and quick and easy insertion of the bit – simply insert and twist into place. SDS-Plus is the most popular variant followed by SDS-Max. When hammer drills are equipped with SDS they are termed ‘SDS hammer drills’ or just ‘SDS Drills’ for short.
Hammer Drill or Rotary Hammer, you can gauge its efficiency by glancing at a few specs. The motor’s power will be designated in watts if it is corded and volts if it is cordless, rotational speed in rotations-per-minute, impact speed in blows-per-minute, and impact energy in joules.
Last update on 2020-10-27 / Affiliate links / Images / Pricing from Amazon Product Advertising API
Let’s take an initial look at our top pick –
Bosch’s compact pro rig performs even more powerfully than its healthy specs indicate, does it consistently, and on top it’s flawless – a perfect ’10.’
Bosch’s corded pro model has an 830-watt motor. It has a speed of 0 to 900 RPMs and an impact rate of 0 to 4,000 BPMs with an impact energy of 2.7 joules. The drilling diameter in concrete is 4 to 26 millimetres.
One and the same model, GBH 2-26, is available in 230 Volts and also 110 Volts with the latter variant meant for usage at construction and development sites.
The bit can be rotated in reverse to ‘unscrew’ it in case of binding, and the rotating brush plate generates equal power in both forward and reverse. An overload clutch cuts off power from the mechanism in case of sudden high resistance.
It has three modes, regular hammer-drilling, drill only, and chisel only. The trigger provides variable speed control and a lock button enables you to maintain a particular speed without depressing the trigger for convenient continuous operation.
The SDS-Plus system allows for tool-free and trouble-free removal and insertion of bits.
The depth stop is up to 210 millimetres.
This is an incredibly powerful and effective rig that makes an easy job of punching through stone, granite, concrete . . . you name it. It can handle thicknesses that many other drill cannot.
The build quality is top class. This kit is compact but powerful, sturdy and reliable . . . you could impact-drill the Colosseum with this dinky beast which weighs only 2.7 kilogrammes.
Bosch has an out-and-out winner with the GBH 2-26; it is one of those rare items for which you have to award a perfect ’10.’
It comes with an auxiliary handle, depth stop and carry case. The only niggle is that the case is not up to the mark, being on the cheap side.
Bosch provides a one-year guarantee extendable to three years if the product is registered within 4 weeks of purchase.
- So powerful is this tool, regardless of the mode, that it makes nonsense of its impressive specs.
- The few features it has, like overload cut-off and speed lock, are flawless in operation.
- Excellent build quality, robust, and durable – built to take knocks and last for many years.
- Not a reflection on the power tool that its carry case is not up to snuff.
Silverline’s hit-or-miss rig has so-so build quality but when it performs it does so admirably, add in the unmatched accessory set and you have VALUE.
Silverline’s corded SDS-Plus hammer drill has 850 watts of power. The rotation speed is 800 RPMs and the impact rate is 4,000 BPMs with a rated impact energy of 3.5 joules which we feel is optimistic. Its drilling diameter in masonry is 26 millimetres.
This DIY kit meant for medium-duty work has hammer-drill, drill only, and hammer only modes. It hits top speed almost immediately, which can catch you off-guard.
Silverline’s 633821 can vary from unit to unit due to dicey quality control. You may get a piece that will keep blazing through concrete and whatever else you put before it and in terms of pure functionality at least compete with the Boschs and the Makitas. On the other hand, your unit may fail after two days or the SDS-Plus’s internal ring may come apart – and if it does you’re out of luck because replacement parts are not provided by the manufacturer.
Speaking of the SDS-Plus, it is dodgy – sometimes bits come loose, sometimes they get stuck, other times you cannot twist them into place.
The build quality and finishing leave something to be desired: the auxiliary handle is flimsy, the metal body is not well moulded, and the plastic controls are cheapish. Then again, this is an ultra-low-priced product so one cannot expect a deluxe product. At 4.58 kilos it is a tad heavy.
Grease must be added to the grease intake compartment before using this drill. A small pot of grease is helpfully included along with a depth stop, dust guard, pin spanner, and a carry case, the latter being rather flimsy. The kit even includes 6-, 8-, and 10-millimetre SDS-Plus masonry drill bits, a flat chisel, and a point chisel. The bits are adequate but professional work should not be attempted with them, nor are they durable. That said, to get a hammer drill and a full complement of accessories at one rock-bottom price makes this an automatic value pick.
Silverline provides a one-year warranty.
- Can knock down a ton of bricks – provided it’s not having one of its moods.
- The generous and complete set of accessories means you’re ready to go.
- The unbeatable rock-bottom price means the missus will appreciate your thrift.
- Dodgy build quality and finishing.
- More dodginess: SDS-Plus is unreliable and can develop some or another defect.
- Replacement parts are not available.
Bringing all the convenience and portability of cordless, Makita’s rig also brings ample power to the table, all topped off with best-in-class user-friendliness.
Makita’s cordless rotary hammer runs on 3, 4, or 5 Ah 18-Volt Li-Ion batteries. It has a rotation speed of 0 to 1,100 RPMs and an impact speed of 0 to 4,000 BPMs with an impact energy of 2 joules. The speed is controlled via the variable-speed trigger. It can drill concrete to 20 millimetres diameter.
This is an SDS-Plus kit.
It has three modes: rotary hammer, rotary only, and hammer only. Whatever the mode and whatever the material – granite, brick, concrete – the DHR202Z makes short work of anything it faces.
Chisels can be locked in 40 different positions.
As good as this concrete cruncher is, it’s the features that make it both user-friendly and safe. The button to toggle between forward and reverse rotation is conveniently positioned. The electric brake is a useful feature. The clutch disengages the motor should a bit bind, and there is a further cut-off to protect the battery circuit from overload. It is also not as loud as comparable rotary hammers.
It even has an LED light.
This crossover tool is something tradesmen might use for medium-duty work and hobbyists can use for even heavy-duty tasks.
In sum, battery-powered this kit may be but it can give a corded kit some stiff competition. It does go hard on the batteries so avoid the 3 Ah ones and go for the 5 Ah’s.
This is a robust and hardy rig and its weight of 3.2 kilos feels just right.
It is sold as body only. Though it comes with an auxiliary handle and a depth stop, the Makpac that Mak-fans so adore is not included. We feel that a kit as excellent as this one should come in the case it deserves.
Makita provides a one-year guarantee extendable to three years if the product is registered within 30 days of purchase.
- Unquestionably powerful, plus cordless means it’s also portable – a big convenience.
- Chock-full of usability and safety features, this baby gets an ‘A’ in user-friendliness.
- While DIYers will be drawn to it, it’s so good many tradesmen will plump for this crossover kit.
- Let alone a Makpac, this kit comes without any case at all.
Fully matching its impressive specs, Dewalt’s three-mode rig has all the best features such as clutch auto cut-off and is lightweight yet strong and sturdy.
Dewalt’s corded hammer drill has 710 watts of power that rotate bits at 0 to 1,550 RPMs and percuss them at 0 to 5,680 BPMs. The impact energy is 2 joules. This hammer drill has a rating of 22 millimetres diameter in concrete.
It operates in three modes: hammer-drill, rotation only, and hammer only.
Speed is controlled by the variable speed trigger. The auxiliary handle can be attached in multiple positions.
With the D25033K you can drill or chisel any masonry with confidence, and its SDS-Plus means you can insert and use bits with total confidence as well.
If this powerful rig hits the proverbial brick wall, it will knock it down! It just keeps on going. But should a bit get jammed, the mechanical clutch will come to the rescue and preclude any sudden high-torque kickback.
This baby dampens vibrations and jarring quite well, which is unexpected in a Dewalt power tool.
At only 2.5 kilogrammes this is a lightweight item yet it has a commendably strong and sturdy build.
For a corded DIY hammer drill with no accessories, we feel that the price needed to be about a fiver less than what it is. Nonetheless, this is a mid-priced SDS-Plus kit which is perfectly suited for medium-duty jobs.
It comes with a depth stop and a carrying case. In view of the competition supplying either flimsy cases or none at all, Dewalt’s very decent case is most welcome.
Dewalt provides a one-year guarantee extendable to three years if the product is registered within 30 days of purchase.
- Dewalt’s power tools’ hallmark is uncompromising power, and this rig is a prime example.
- Sharp design such as the multi-position auxiliary handle and vibration damping.
- Though lightweight and compact, it is unexpectedly also very sturdy and robust.
- No real con but only a quibble: as a cordless DIY kit without accessories, it may be a touch overpriced.
This Bosch rig is power packed yet easy to use for DIYers, making it a bargain at its price; no wonder it is Amazon’s top-selling rotary hammer drill.
The 550 watts of Bosch’s corded rotary hammer rotates the bit at 0 to 2,300 RPMs and percusses it at 0 to 5,800 BPMs. It has an impact energy of 1.7 joules.
This SDS-Plus rotary hammer has a pneumatic hammer mechanism and has an un-advertised soft start.
It has four modes: hammering, chiselling, drilling and screwdriving. The speed is controlled by the variable-speed trigger. The chisel bit can be secured in 36 positions. It is rated to 20-millimetre diameter in concrete which it handles with ease. And not only concrete, it does some serious damage to brick, flagstones, or cinder blocks. For a DIY kit, its performance is simply ‘smashing’.
The one niggle is that every now and again the clutch acts up; it becomes over-sensitive and reacts too quickly to minor resistance.
The PBH 2100 is powerful yet light at only 2.2 kilogrammes and its soft-grip handles make things even easier. Moreover, it is relatively quiet and has relatively low vibrations. It is the perfect light-to-medium-duty rotary hammer for home use but it is also robust and very durable.
It comes with an auxiliary handle, a depth stop and a plastic carrying case.
This is not only a top-quality DIY power tool, the price is so downright reasonable that, quite amazingly, a Bosch outfit can rightly be called a great value for money. Not too surprising then that it is at the top of the heap on Amazon’s Top Tens in both Rotary Hammers and Hammer Drills – a double #1 ranking.
Bosch provides a two-year guarantee, provided the tool is not used for professional or trade purposes, extendable to three years if the product is registered within 4 weeks of purchase.
- No matter the mode or the material, this rig’s performance is absolutely ‘smashing.’
- In view of its ease-of-use, besides its power, at the price it is a real bargain.
- Number 1 in both Rotary Hammers and Hammer Drills on Amazon – that says it all.
- The over-sensitive clutch acts up now and then – and cuts off power when it encounters a bit of resistance.
How To Operate A Hammer Drill
Let’s say you want to drill a 10-millimetre hole in a concrete wall.
As preliminary steps, mark the point at which you want to drill and select and insert the appropriate drill bit in the chuck or SDS. Use only bits meant for hammer drills; typically they will be carbide-tipped or carbide.
Next, decide the depth to which you want to drill. Then either attach the supplied manual depth stop or tape a strip of insulating tape at a measured position on the bit itself to serve as a visual guide.
Now put on your safety goggles, ear protection, and gloves.
Grasp the drill by the handle with one hand. Hold the auxiliary handle, if there is one, with the other hand, otherwise use your other hand to brace the drill by grasping it from the bottom a little in front of the first hand.
Stand with your feet about shoulder-width apart, maintaining a good balance with a slight forward lean, and rest the tip of the bit at the point to be drilled but without exerting pressure.
Though you will not be exerting pressure, maintain a stiff grip, especially with the second, bracing hand – if the bit binds and the drill does not have an automatic clutch-disengage function, you may experience a nasty rotational kickback that can injure your wrist.
Turn on the drill, pressing the trigger gently to operate the drill at a slow speed initially.
Maintain a firm hold with slight pressure but unlike a traditional drill, you do not need to exert any real pressure or force.
Maintain the slow speed, making sure the bit is drilling into the marked spot and there is no bit ‘run.’
As the hole becomes established and the bit is getting bored in, increase the speed.
If the bit gets bound (i.e. stuck or jammed), possibly because of swarf and debris build-up, release the trigger, and pull out the drill if possible or flip the reverse switch and start again so as to ‘unscrew’ the bit. Clean out the grooves and flutes of the bit. Puff a few jets of canned air into the hole while holding a hand-held vacuum in the other hand to clear out the hole.
Continue until done.
Will An SDS Hammer Drill Break Concrete?
It can, but that’s neither its forte nor what it’s meant for. Though it can break concrete, an SDS Hammer Drill is made to make holes of a particular diameter and length into concrete and other masonry. You would do this when you want to install smaller fittings like hooks, dowels, meter-boxes, switchboards, etc. in masonry walls. It is also used to cut channels with a chisel in hammer-only mode. You can use it in this same mode to break up a layer of concrete when it is holding something, like a post, in place. You really cannot use it to break up a concrete driveway or patio.
To actually drill right through concrete, including old, hardened concrete, you could use an SDS Rotary Hammer, preferably in hammer/impact only mode. It is simply more powerful than a Hammer Drill. Use chisel bits to break into or break up concrete.
If you want to break up largeish concrete surfaces or small concrete structures so as to demolish them, use a concrete breaker aka demolition hammer.