Will an SDS Plus bit fit an SDS Max machine?

Not directly. SDS Plus has a 10 mm shank and SDS Max an 18 mm one, and they are different systems. Adapters exist mainly to run smaller bits in a larger machine, not the other way round.

Why is my combi drill so slow in concrete?

Because a three jaw chuck grips the bit tight, so hammer mode shakes the whole tool rather than striking the bit. An SDS machine lets the bit slide and hits the end of it directly, which puts far more energy into the tip.

Can I use a masonry bit on tile?

On soft ceramic with hammer action off, sometimes. On porcelain and hard tile use a diamond bit instead, because a carbide chisel tip shatters the glaze and wanders before it bites.

Can masonry drill bits be sharpened?

Yes. Carbide can be dressed on a green silicon carbide wheel, keeping the original tip angle. What cannot be recovered is a tip overheated to blue, because the braze holding it in has softened.

What size hole does a wall plug need?

The size printed on the plug, not the screw diameter. Those are two different numbers, and drilling to the screw size gives a hole the plug will not enter while going oversize lets it spin.

Why does my bit stop advancing part way down?

Packed dust in the flutes. Withdraw the bit every few centimetres to clear it. Pushing harder instead generates heat, and heat is what softens the braze holding the carbide tip.

Concrete and Masonry Drill Bits

Author: James Whitfield, Equipment Desk5 min read27 September 2026

Updated 30 August 2026

A masonry bit does not cut like a twist drill. A brazed tungsten carbide tip crushes and grinds the material while the flutes clear the dust, and hammer action supplies the blows that do most of the work. Choose on two things: the shank your machine takes, and whether the tip is a plain carbide chisel or a multi-cutter head.

5 products from £25.99 to £67.99

Four masonry drill bits of increasing diameter standing upright on a concrete block beside a drilled hole

Specs and prices

Specifications as declared by the seller of each listing, not our own measurements. Prices update with the catalogue.

Product	Price	Shank Type	Product Type	Material	Working Length	Application
Masonry Drill Bit Set	£67.99	Round	-	-	60 mm	-
Premium Professional Masonry Drill Bit SDS Plus	£42.99	-	-	Steel with Ergonomic Grip	-	-
Masonry Drill Bit Set	£29.99	Triangle (SDS-Plus compatible)	Masonry Impact Drill Bit	Tungsten Carbide Tip, Steel Body	-	Concrete, Masonry, Brick
3/4/7PCS Drill Bit Set Glass Concrete Drill Bit Set Masonry Drill Bits for Brick Plastic and Wood Hex Shank Tip Drilling Tools	£26.99	Hexagonal	Drill Bit Set	High-Speed Steel with Carbide Tip	-	-
SDS Plus Drill Bits	£25.99	SDS Plus	SDS Plus Rotary Hammer Drill Bit	Carbide-Tipped Steel	110 mm, 160 mm, 210 mm, 350 mm, 500 mm	Masonry, Concrete, Brick, Block

The shank decides which machine it fits

A plain round or hex shank goes into an ordinary three jaw chuck, which is what a combi drill or a cordless drill takes. The chuck grips the bit tight, so any hammer action has to shake the whole tool, and that is why a combi drill in hammer mode is slow in concrete and tiring to use.

SDS is a different idea. The shank has open grooves and the chuck locks into them while letting the bit slide back and forth a few millimetres, so a piston inside the tool strikes the end of the bit directly. Almost all the energy reaches the tip instead of shaking the operator, which is why an SDS machine drills concrete several times faster than a combi drill.

SDS Plus and SDS Max are not the same system. SDS Plus has a 10 mm shank and suits the common cordless and corded rotary hammers; SDS Max has an 18 mm shank and belongs on larger breakers and heavy rotary hammers. They do not interchange, and adapters exist mainly to put smaller bits in bigger machines rather than the reverse.

Matching the bit to the machine
Shank	Fits	Best at
Round or hex	Ordinary drill chuck	Small holes, brick, occasional work
SDS Plus, 10 mm	Standard rotary hammers	General concrete and masonry drilling
SDS Max, 18 mm	Large rotary hammers, breakers	Big diameters and deep holes

Carbide tips, and where a multi-cutter earns its cost

The working end is a piece of tungsten carbide brazed into a steel body. Carbide is very hard and quite brittle, which is exactly right for crushing aggregate and exactly wrong for prying, so a bit that has been levered in a hole tends to lose its tip rather than bend.

The traditional shape is a single chisel across the diameter. It is cheap, it works, and it is thrown off line when it meets a piece of hard aggregate or a reinforcing bar at an angle. Multi-cutter heads, with four cutting edges or a cross form, stay centred far better, break through aggregate more cleanly and leave a rounder hole, which matters when the hole is for a resin anchor.

A blunt masonry bit is often recoverable. Carbide can be dressed back to a clean edge on a green silicon carbide wheel, keeping the original tip angle, and a resharpened bit cuts far better than a rounded one. What cannot be fixed is a tip that has been overheated to blue, because the braze holding it in will have softened.

When hammer action helps and when it ruins the hole

Concrete, block and hard brick all want hammer action, because the blow is what fractures the material ahead of the tip. Without it you are relying on the carbide to abrade its way through, which is slow and cooks the tip.

Soft or brittle materials want the opposite. Hollow blocks blow out on the far side under hammering, soft brick crumbles into an oversized hole that will not hold a plug, and glazed tile shatters. Switch to rotation only for those, and use a diamond bit rather than a masonry bit for porcelain and hard tile.

The technique that keeps a bit alive is to let the tool do the work and withdraw the bit every few centimetres to clear dust. Packed dust in the flutes stops the bit advancing, which tempts more pressure, which generates heat, which is what softens the braze. On deep holes clearing regularly is faster overall as well as kinder to the bit.

Diameter, length and drilling for a fixing

Match the bit diameter to the fixing rather than to the screw. A plastic plug states the hole size it needs and the screw size it takes, and those are two different numbers. Drilling to the screw diameter gives a hole the plug will not enter; going oversize gives a plug that spins.

Working length matters as much as overall length. The usable depth is the fluted section, not the whole bit, so a 160 mm bit does not drill a 160 mm hole. Where a fixing needs a specific embedment, check the flute length and allow for the dust that collects at the bottom.

Drill deeper than the fixing needs and clear the hole properly before setting anything in it. Dust left at the bottom stops a plug seating and, with resin anchors, it is the single most common reason a fixing pulls out well below its rated load. A blow pump or a vacuum is worth having for anything structural.

James WhitfieldEquipment Desk

James edits the machine and equipment buying guides. The specifications on these pages are the declared figures from the live listings we hold, with a note wherever a number comes from a published standard instead. Pages are re-checked as the catalogue changes.

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