Independent comparisons. We may earn from shop links. More info

Cutting metal with a cordless angle grinder

Updated: October 2026

You need to cut a bolt, a bracket or a piece of thin steel, and the cordless grinder is already on the bench. The cut goes wrong when the thin disc is used on its side, when the pack dies in the kerf, or when a 76 mm mini is asked to keep going through thick bar. Cutting metal with a cordless angle grinder means a metal cutting disc marked fast enough for that body, kept in the cut. Fitting any disc is the [how to use page](/hub/sanders/cordless-angle-grinder/sub/cordless-angle-grinder-how-to-use). Depth between 115 mm and 125 mm is the [115 mm or 125 mm page](/hub/sanders/cordless-angle-grinder/sub/cordless-angle-grinder-115-vs-125). Which body you buy is the [cordless angle grinder comparison](/hub/sanders/cordless-angle-grinder).

You need to cut a bolt, a bracket or a piece of thin steel, and the cordless grinder is already on the bench.

Our top picks

DeWalt DeWalt DCG407N-XJ 125 mm bare

Best overall

DeWalt DeWalt DCG407N-XJ 125 mm bare
9.4/10about £107.50
View offer
TEENO TEENO 76 mm mini kit

Rank 2

TEENO TEENO 76 mm mini kit
8.8/10about £39.99
View offer
DCA DCA ADSM06-125 125 mm kit

Best value

DCA DCA ADSM06-125 125 mm kit
8.6/10about £56.98
View offer
On this page
  1. 1.The disc, not the grinder brand
  2. 2.What a cut feels like on these tools
  3. 3.Sparks, clamps and a second pack
  4. 4.When to stop using a cordless grinder

The disc, not the grinder brand

Buy the wheel for the metal, then check it against the grinder. A Type 41 disc is flat and is the cutting shape. A Type 27 has a depressed centre and is the grinding shape. Kayson Green, a disc seller, suggests about 1 mm to 1.6 mm for mild steel and stainless, and about 1.6 mm to 2.5 mm on thicker stock. That is seller guidance, not a standard clause. Trend UK describe a 1.0 mm kerf as easier on a cordless pack, with a 22.2 mm bore on 115 mm Type 41 discs. The wheel must show a maximum rpm, under EN 12413, that clears the grinder. If the number is lower, do not fit it. Keep the disc in the cut. BuildWiz is explicit that you do not use a cutting disc sideways, because side load shatters a thin wheel. If the kit's cutting wheel is vague, buy a marked Type 41 first.

What a cut feels like on these tools

A bolt or a thin bracket is the job these cordless bodies can do. Thick bar is where the limit appears. The TEENO listing says the 76 mm tool is not for continuous thick metal. A mini can nip a small bolt as light DIY, then it should stop. SoarFly's bullets claim rebar at top speed. That sentence is the manufacturer's, and this page does not promise rebar from it. Two 4.0 Ah packs change the wait between charges. They do not change the bar. If the first disc glazes or wanders, replace it with a Type 41 marked for the rpm.
DeWalt DeWalt DCG407N-XJ 125 mm bare

Testsieger

DeWalt DeWalt DCG407N-XJ 125 mm bare
9.4/10about £107.50
View offer

Sparks, clamps and a second pack

Sparks travel further than the disc, and they land hot. Electrical Safety First covers sparks, a clamp, and eye and hand protection. Clamp the piece so it cannot spin into the wheel. Point the guard away from your hands and anything that will burn. Let the disc reach speed first, and ease off if a steady fan of sparks turns into a violent spray. BuildWiz states the cordless limit: the tool stops when the pack stops. When the tool slows in the kerf, lift out while it still turns, then take the battery off. Forcing a dying disc through the last of the cut is how the wheel grabs.

When to stop using a cordless grinder

Stop when the section is structural. A heavy RSJ or a beam you cannot clamp is a 230 mm cutter, which is the line BuildWiz draws. Stop when a cutting disc is being asked to grind a weld, and stop when a 76 mm mini is past a light nip. This page is from the Products Compared editorial team, updated on 15 October 2026. Kayson Green's thicknesses are seller guidance. Runtime figures are reviewer reports, not a lab cut. A qualifying purchase through our links can earn a commission at no extra cost to you.

Common questions

Can I grind a weld with the cutting disc?
No. The cutting disc stays in the kerf. Grinding a weld loads the face and the side, which BuildWiz tells you not to do. Use a flap disc or a grinding wheel for finishing, with the guard position for that job. Flap discs in the DCA and Dong Cheng kits are for finishing. They do not slit the steel.
Will a cordless grinder cut rebar?
It might cut a short, thin piece if the disc is a proper metal cutting disc and the pack lasts the pass. SoarFly's bullets claim rebar at the tool's top speed, and that claim is the manufacturer's sentence, not a result we repeat as fact. Thick or continuous bar is where these kits run out of honesty. If the bar is structural, use a 230 mm cutter.
Is a 76 mm mini able to cut a bolt?
A small bolt, as light DIY, is the job a mini such as the TEENO is written for. The same listing says it is not for continuous thick metal. The bore is not the full-size trade bore, so you cannot fit a standard 115 mm or 125 mm cutting disc and call the problem solved. One bolt in a corner is plausible. A run of heavier fixings needs a full-size body.
Are the discs in a £60 kit good enough?
Treat them as a starter. The DCA kit includes cutting and flap discs at £56.98, and NANWEI buyers in this set have already called some included discs useless. A wheel in the case has not been matched to your rpm mark or to your steel. If it glazes, replace it with a marked Type 41. Keep any flap disc for finishing only.
Why does the cut stop halfway?
Usually the pack is flat or the disc is pinched. DCA reviewers report about 20 to 30 minutes, not the longer manual claim, so a single 4.0 Ah pack can die mid-bar. A second pack changes the wait. It does not thicken the steel you can cut. Lift the disc out while it is still turning, then take the battery off, and do not lean on a stalled wheel.

Related pages

Sanders

Cordless angle grinder

115mm or 125mm angle grinder: which disc and guard

Best cordless angle grinder UK for XR packs or a kit

Cordless angle grinder buying guide for kit or body

How to use a cordless angle grinder: disc and guard

Sources

Public UK sources named for workplace guards, abrasive wheels, vibration, and the grinder standard. amazon.co.uk prices, stars, and review counts are the figures stored for these twelve listings. Prices move.

  1. HSE, PUWER overview (retrieved October 2026)
  2. HSE, HSG17, Safety in the use of abrasive wheels (retrieved October 2026)
  3. HSE, INDG175, hand-arm vibration (retrieved October 2026)
  4. Control of Vibration at Work Regulations 2005, regulation 4 (retrieved October 2026)
  5. IEC 62841-2-3:2020, particular requirements for hand-held grinders (retrieved October 2026)
  6. OSA, EN 12413 marking note for bonded abrasives (retrieved October 2026)
  7. Electrical Safety First, angle grinders (retrieved October 2026)