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230mm diamond cutting disc: what to check before you pay

Updated: 21 October 2026

You already have a 9 inch angle grinder, or you are hiring one for a patio, and the search for a 230mm diamond cutting disc is full of wheels that look the same in the thumbnail. The useful order is the machine, the hole, the rim, the speed mark, and a dust plan, before the star row. Shelf prices in the [230mm diamond cutting disc comparison](/hub/sanders/230mm-diamond-cutting-disc) run from £8.99 to £84.43 on amazon.co.uk. This page is the checklist. The Products Compared editorial team read those twelve listings on 19 October 2026. We did not cut a slab. A qualifying Amazon purchase can earn a commission at no extra cost to you.

You already have a 9 inch angle grinder, or you are hiring one for a patio, and the search for a 230mm diamond cutting disc is full of wheels that look the same in the thumbnail.

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What you are actually buying

A 230 mm diamond cutting disc is a steel wheel with a diamond rim, sold in the UK as a 9 inch diamond blade. It belongs on a grinder or cut-off saw rated for that diameter, with the guard in place. People buy one to cut concrete, brick, block paving, kerbs, and patio slabs. It is not a thin abrasive cut-off wheel for steel, and it is not a continuous-rim tile blade. The twelve listings are mostly segmented general-purpose discs. Two are turbo or turbo-segmented. A bullet that says reinforced concrete means the disc may meet a bar while cutting concrete. It does not mean a metal-cutting wheel.

Machine, guard, and the hole

A 230 mm disc needs the guard made for a 230 mm grinder. Moving the guard so the disc fits a smaller machine side-loads a rim it was not built for. A 115 mm or 125 mm grinder is the wrong size. The Bosch turbo listing is the awkward case: the Amazon title says small grinders, the highlight says Ø 230 mm, and Bosch Professional UK lists part 2608602397 as 230 mm. Trust the diameter on the disc. The hole is 22.23 mm. Some listings round that to 22.2 mm. M14 is the spindle thread, not the hole. PRODIAMANT’s bullet pairs a 22.23 mm bore with M14, which mixes the two. A disc that sits loose is a stop. Fitting steps are on how to use a 230mm diamond blade.

Rim, segment height, and speed

Segmented rims are the general masonry choice. Gaps clear dust and let the rim cool. A turbo rim is a faster, more aggressive edge. Norton’s UK note puts a continuous rim on a cleaner tile edge, and this set barely sells that edge. The choice is on segmented vs turbo diamond blade. Heights in the bullets are 7 mm on PRODIAMANT, 10 mm on S&R and the OX twin pack, 12 mm on DeWalt, and 15 mm on the OX turbo and the Bosch EXPERT scope line. A taller segment is more diamond depth, not a measured life. The OX twin-pack cell that says 230 mm of segment is the diameter. Use the 10 mm bullet. Stay under the lower of the disc mark and the spindle mark. A blank speed cell is a gap, not permission to run flat out.

Marks, dust, and when this is the wrong tool

EN 13236 is the superabrasive standard. FEPA says a diamond saw for an angle grinder up to 230 mm should conform and be marked, and that you should inspect the disc before you fit it. Only PRODIAMANT, Blue Spot, and Tech Traders say so in these listings. Silence is a scrape gap, not a verdict, and a printed mark is not a promise that a cheap rim stays in one piece. Concrete, brick, mortar, and stone make respirable crystalline silica. HSE’s workplace exposure limit is 0.1 mg/m³ over 8 hours. The controls are water or an M-class or H-class extractor, plus respiratory protection at APF 20. Stop if a segment cracks, the disc wobbles, or the core looks blue from heat. Call a professional for structural concrete, a dropped or burst disc, and any site where you cannot set exclusion, extraction, and respiratory protection.

Common questions

Is 22.2 mm the same bore as 22.23 mm?
On these listings, 22.2 mm is the rounded form of the 22.23 mm hole used with a standard locking nut. S&R and Tech Traders print 22.2 mm. Most of the Bosch and OX rows print 22.23 mm. If the disc rattles on the spindle, stop. Do not pack the hole with a loose washer.
Why does Amazon show the wrong thickness?
The item-thickness field is often filled with another dimension. DeWalt’s field reads 22.23 mm, which is the bore. One Bosch field reads 23 mm, which is the diameter in centimetres written as millimetres. The OX turbo field reads 15 mm, which is the segment height. Use a cutting width only when a bullet states it, such as Tech Traders’ 2.2 mm line.
Do I need an EN 13236 mark?
FEPA recommends that diamond saws on angle grinders conform to EN 13236 and carry the mark. Only three listings in this set say they do: PRODIAMANT, Blue Spot, and Tech Traders. A missing line is not proof the disc is unmarked in the box, and a printed line is not proof a segment will stay on. Inspect the rim anyway.
What speed must I stay under?
Stay under the lower of the disc mark and the grinder mark. FEPA’s 80 m/s band is about 6,650 rpm on 230 mm. Blue Spot states 6,600 rpm and Tech Traders states 6,650 rpm. If your plate is lower, use the plate. A blank speed cell is a reason to read the grinder plate, not a reason to ignore it.
Can I cut dry indoors?
Dry cutting in a closed room puts silica dust into the air you breathe. HSE’s controls are water, or M-class or H-class extraction, plus respiratory protection at APF 20. A weekend patio outside still needs a dust plan. An indoor chase without that kit is a job for someone equipped for it.

Related pages

Sources

Sources taken from the research digest. Listings were checked on 19.10.2026.

  1. HSE — Scabbling or grinding (retrieved 19.10.2026)
  2. HSE — CIS54 Respirable crystalline silica (retrieved 19.10.2026)
  3. HSE — CN6 Cutting paving and kerbs (retrieved 19.10.2026)
  4. HSE — CN2 Chasing with hand-held tools (retrieved 19.10.2026)
  5. HSE — HSG17 Safety in the use of abrasive wheels (retrieved 19.10.2026)
  6. FEPA — Diamond saws on angle grinders (retrieved 19.10.2026)
  7. Norton UK — Segmented versus continuous diamond blades (retrieved 19.10.2026)
  8. Bosch Professional UK — 2608602397 turbo disc (retrieved 19.10.2026)