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Diamond core bit buying guide

Updated: 2026-10-23

You are about to cut one hole in a UK house, a waste through a tiled wall or a duct through brick, and the amazon.co.uk results all say diamond core bit. A £12.99 coated cup and a £47.99 barrel can sit on the same screen. They are not the same tool. This diamond core bit buying guide separates the job, the diameter, the thread in the box, and the cooling the listing states, before a concrete bullet chooses for you. The drill stays in rotation only. Prices and the twelve rows stay on the [diamond core bit comparison](/hub/drilling-and-accessories/diamond-core-bit).

You are about to cut one hole in a UK house, a waste through a tiled wall or a duct through brick, and the amazon.co.uk results all say diamond core bit.

Our top picks

MOXPIFY MOXPIFY 52 mm core bit set

Best overall

MOXPIFY MOXPIFY 52 mm core bit set
8.1/10about £31.99
View offer
Starrett Starrett BMC117 117 mm dry core

Alternative

Starrett Starrett BMC117 117 mm dry core
7.9/10about £29.91
View offer
SHDIATOOL SHDIATOOL 6 mm dry diamond tile bits

Rank 3

SHDIATOOL SHDIATOOL 6 mm dry diamond tile bits
9.2/10about £28.99
View offer
On this page
  1. 1.Barrel or cup
  2. 2.Diameter against the fitting
  3. 3.Thread, shank, and what is in the box
  4. 4.Cooling and the material line
  5. 5.What the twelve listings still leave open

Barrel or cup

Start with the material the rim will touch. A masonry barrel is a hollow steel tube with diamond segments and a centre pilot. It takes a plug out of brick or block. A tile cup is short, coated or vacuum-brazed, for ceramic or porcelain. It has almost no depth, so a similar title will not carry a waste through masonry. On the 19 October 2026 amazon.co.uk shelf, the Meccion 40 mm coated cup was £12.99 and asks for water, while the MOXPIFY 107 mm barrel was £47.99. The SALI 52 mm, at £34.99, is laser-welded and prefers dry cutting.

Diameter against the fitting

Match the bit to the outside of the fitting, with room for a fall and a socket, not to the nominal size on the pipe. A 110 mm soil pipe is not a 110 mm bit. Here, 44 mm and 52 mm sit with small wastes, and 107 mm and 117 mm with flues, vents and soil-size holes. Guides disagree between 117 mm and 127 mm. Measure the fitting on the diamond core bit for a soil pipe page. Barrels here are listed at 150 mm, 170 mm or 240 mm. The DaduoRi Pro is 52 mm by 240 mm, at £46.99. Do not add the adaptor and call the sum a measured depth. Around 107 mm and above, or where a detector marks a service, call a professional.
MOXPIFY MOXPIFY 52 mm core bit set

Testsieger

MOXPIFY MOXPIFY 52 mm core bit set
8.1/10about £31.99
View offer

Thread, shank, and what is in the box

A 1/2 inch BSP thread does not mean the bit fits the SDS drill you own. A kit may add an SDS Plus adaptor, a hex adaptor and a drift, and that adaptor still has a size limit. Armeg's February 2024 dry-core sheet says not to use an SDS Plus adaptor with 107 mm and 127 mm cores. The same brand's product page names 117 mm and 127 mm instead. M14 fits a small tile bit on a 115 mm or 125 mm angle grinder, unless a hex adaptor and a drill speed are stated. FACHLICH's 11-piece kit, at £109.99, includes a hex adaptor. INQUIRLLY's 12-piece set was £22.99 and does not state the shank. The title stops at 50 mm while a contents bullet includes 68 mm. The Starrett BMC117 is a 117 mm bit only, at £29.91. A straight shank needs a chuck or an arbor the box does not include.

Cooling and the material line

Dry cutting with dust extraction suits facing brick and block. Wet coring in concrete wants a real water feed and a slurry plan. Wax in a small vacuum-brazed bit is the dry method for porcelain. The Meccion cup asks for water. The SALI 52 mm prefers dry. The MOXPIFY barrels are labelled wet or dry. The DaduoRi Pro states no cooling method. DaduoRi's 44 mm barrel excludes concrete and stone, and a concrete bullet does not overrule that exclusion. None of these listings states BS EN 13236. Choose water, wax or extraction on the wet or dry diamond core bit page.

What the twelve listings still leave open

The shelf will not tell you which bit lasts. The DaduoRi 44 mm file has no review line. The three MOXPIFY files share one 4.7 from 83. That shared line is not three endurance tests. If a card contradicts itself, believe the exclusion and the contents list.

Common questions

Is a diamond core bit the same as a tile hole saw?
No. The tile hole saw here is the short cup for ceramic or porcelain. The masonry bit is the steel barrel with segments. A tap hole in tile wants the cup, and a waste through brick wants the barrel.
What should you match before the diameter?
Match the family first: a barrel for masonry, or a cup for tile. Diameter comes next, against the outside of the fitting. Thread and cooling follow. A 40 mm cup and a 52 mm barrel are not the same tool.
Does 1/2 inch BSP mean the bit fits the SDS drill you own?
Only if an SDS Plus adaptor is included, or you already own one, and only inside that core's size limit. Armeg's sheet says not to use one with its 107 mm and 127 mm cores. Its product page names 117 mm and 127 mm. Read the line for the bit in your hand.
When is M14 the fitting, and is the hex adaptor in the box?
M14 suits a small angle grinder. Use a drill only when that listing includes a hex adaptor and a drill speed. FACHLICH's kit includes the adaptor. INQUIRLLY does not state the shank.
Why is a straight shank a different purchase from an SDS set?
The Starrett is the core alone. An SDS set is a 1/2 inch BSP barrel plus the adaptor. At £29.91 it can undercut the £47.99 MOXPIFY 107 mm only if you can already drive that shank.
Can a bullet that says concrete overrule a line that excludes it?
No. DaduoRi's 44 mm listing excludes concrete and stone. A wet-or-dry label does not erase a dry preference, or a card that states no cooling method, as on the DaduoRi Pro. Where title and contents disagree, use the narrower line.

Related pages

Best diamond core bit

How to use a diamond core bit

Diamond core bit

Diamond core bit for a soil pipe, 117 mm or 127 mm

Wet or dry diamond core bit: the right cooling method

Sources

Public UK sources from the research digest, last checked on 20 October 2026. Shelf prices and star lines are the amazon.co.uk figures in the display file.

  1. HSE CN8, Diamond coring/hole cutting (retrieved 20 October 2026)
  2. HSE CN3, Drilling with hand-held rotary tools (retrieved 20 October 2026)
  3. HSE CIS65, Cable detection and isolation (retrieved 20 October 2026)
  4. BSI, BS EN 13236:2019 superabrasive safety (retrieved 20 October 2026)
  5. Mexco wax-filled M14 diamond tile drills (retrieved 20 October 2026)
  6. Premier P6-ATDM14 diamond tile drill sheet (retrieved 20 October 2026)
  7. Armeg dry-core instructions (retrieved 20 October 2026)
  8. Toolstation diamond core drill bits (retrieved 20 October 2026)