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How to use an SDS plus rotary hammer

Updated: 22 October 2026

You have a blue Bosch Professional SDS-plus hammer, a masonry bit, and a wall that a combi drill has already polished. The next few minutes decide whether the hole stays round, whether the fixing seats, and whether you find a cable. Fit the side handle, find the services, seat the bit, then let the piston work without you leaning through the trigger. These steps follow the eight tools in the [Bosch professional SDS drill comparison](/hub/drilling-and-accessories/bosch-professional-sds-drill), from the 1.5 J GBH 18V-18 to the 3.2 J GBH 2-28. They were set out on 19 October 2026 from Bosch manual points and HSE guidance. There was no lab test. A qualifying purchase can earn a commission at no extra cost to you.

You have a blue Bosch Professional SDS-plus hammer, a masonry bit, and a wall that a combi drill has already polished.

Our top picks

Bosch Bosch Professional GBH 18V-18

Best overall

Bosch Bosch Professional GBH 18V-18
7.5/10about £122.95
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Bosch Bosch Professional GBH 2-21 (230 V)

Rank 2

Bosch Bosch Professional GBH 2-21 (230 V)
9.4/10about £120.15
View offer
Bosch Bosch Professional GBH 2-28

Alternative

Bosch Bosch Professional GBH 2-28
7.6/10about £253.21
View offer
On this page
  1. 1.Set the tool up before the trigger
  2. 2.Drill the hole
  3. 3.Chisel only on the models that have the mode
  4. 4.Stop for services, dust and vibration

Set the tool up before the trigger

Do not run a GBH 2-21 without the auxiliary handle. The handle is how you resist the twist if the bit binds. A 2.3 kg GBH 2-21, or the GBH 2-28 at 3.24 kg, is a two-hand tool. KickBack Control, where it is stated, cuts the motor if the tool suddenly spins. In this set that is the GBH 18V-18, both 18V-22 models, the 18V-18 X and the GBH 2-28. If it trips, release the trigger and press it twice. The two GBH 2-21 listings do not state that feature. Seat the bit before the depth stop: draw the sleeve back, push the SDS-plus shank in until it clicks, let the sleeve return, then tug. ONECHUCK also clamps a cylindrical or hex shank, limited to 10 mm straight shanks on the GBH 18V-18 X. SDS-max bits do not fit. If the plug is yellow, stop. A 110 V GBH will not run from a BS 1363 socket. That question is the 110 V site page.

Drill the hole

Select hammer drilling for brick, block or concrete. Rotate-only is for wood, metal, ceramic or plastic. Hammer-only is chiselling, and only on models that have that mode. Let the piston supply the blow. UK reviewers say a 2.0 J GBH 2-21 goes into concrete after a combi has stalled, and it will also go through a pipe if the tone changes and you stay on the trigger. If progress falls off, clear the flutes. On a 230 V tool at home, plug in through an RCD. Stop if the tone becomes a metallic ring or the bit runs free. The depth stop only knows the distance you set. Whether the hole should have been cordless is the corded versus cordless page.
Bosch Bosch Professional GBH 18V-18

Testsieger

Bosch Bosch Professional GBH 18V-18
7.5/10about £122.95
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Chisel only on the models that have the mode

Chiselling is a separate mode, not a harder lean on hammer drilling. The GBH 2-21 listings state hammer drilling, drilling and chiselling. Bosch’s pages for the GBH 18V-22 and the GBH 18V-22 X also describe chiselling. The GBH 18V-18 and GBH 18V-18 X do not. UK reviews of the larger cordless hammers talk about tiles and a short chase, and they say serious breaking needs a bigger Bosch than the GBH 18V-22. Set hammer only, lock a matching chisel, and keep the side handle on. If you are on the GBH 18V-18 and the job has turned into tiles, stop. That limit is the buying guide. If the dial will not move, that is a return, not pliers on the collar.

Stop for services, dust and vibration

Look at both sides of the wall. Electrical Safety First and the Health and Safety Executive say to treat cable routes as real, to use a detector while remembering that detectors miss some cables, and to switch the circuits off.An RCD does not find the cable. If the work is structural, call someone whose job is that opening. Concrete dust can contain respirable crystalline silica. HSE sheet CN3 wants extraction or respiratory protection at APF 20. A Bosch data sheet for the GBH 18V-18 declares about 97 dB(A), above the noise action values.Do not copy that figure onto every GBH. Declared hammer-drilling vibration, K of 1.5 m/s², runs from about 18.7 m/s² on the GBH 18V-18 to about 11 m/s² on the GBH 2-28. The action value is 2.5 m/s² A(8) and the limit is 5.

Common questions

How do I lock an SDS plus bit?
Draw the locking sleeve back, push the SDS-plus shank fully home, and let the sleeve return until the bit clicks. Tug it. If it pulls out, it was not seated. SDS-max shanks do not lock in these noses. ONECHUCK also clamps a straight or hex shank, up to 10 mm on the GBH 18V-18 X.
How do I set the depth stop on a Bosch GBH?
Seat the bit first. Measure from the tip after the click, and slide the stop rod to that distance. A 70 mm frame fixing is an example of the method, not a Bosch capacity. The stop does not know about a pipe behind a thin wall.
Can I use it one-handed?
No. Bosch’s GBH 2-21 guidance is not to run the tool without the auxiliary handle. KickBack Control, on the models that state it, cuts the motor if the tool spins. Reset it by releasing the trigger and pressing twice. That is a backstop, not a one-hand mode.
How do I avoid cables and pipes?
Look at both sides of the wall, stay off the straight runs from sockets, switches and radiators, and use a detector while treating a clear reading as incomplete. Detectors miss some cables. Switch the circuit off and use an RCD. If you cannot account for what is in the wall, do not drill it.
What if the bit will not come out?
Stop the motor, draw the locking sleeve, and withdraw the bit. Do not keep the trigger in to spin it loose, and do not beat the holder. Reviews mention a bit that stuck, including on the GBH 18V-18. If the sleeve will not free it, the holder is jammed and that is a repair.
How long can I hammer before a break?
There is no single minute count. HSE’s illustration of about 15 minutes is for tools around 15 m/s². The GBH 18V-18 is about 18.7 m/s² and the GBH 2-28 about 11 m/s², so use the figure on your own tool.

Related pages

Best Bosch professional SDS drill

Bosch professional SDS drill

Choosing a 110 V or 230 V Bosch SDS drill in the UK

Bosch Professional SDS drill: joules, then the box

Corded vs cordless Bosch SDS drill, with the battery

Sources

Public UK sources from the research digest, last checked on 19 October 2026. Shelf prices and star lines are the amazon.co.uk figures in the display file.

  1. Bosch UK, GBH 2-21, 0 611 2A6 071 (retrieved 19 October 2026)
  2. Bosch UK, GBH 2-28, 0 611 267 571 (retrieved 19 October 2026)
  3. Bosch UK, GBH 18V-18, 0 611 927 000 (retrieved 19 October 2026)
  4. Bosch UK, GBH 18V-22 and GBH 18V-22 X (retrieved 19 October 2026)
  5. HSE, hand-arm vibration regulations (retrieved 19 October 2026)
  6. HSE, construction dust sheet CN3 (retrieved 19 October 2026)
  7. Control of Noise at Work Regulations 2005, regulation 4 (retrieved 19 October 2026)
  8. HSE, electrical systems on construction sites (retrieved 19 October 2026)