Toothed saw blade on an angle grinder: UK alert

You have a fence post to trim, a 125 mm angle grinder, and a basket that says "wood blade for angle grinder". A toothed saw blade on an angle grinder is what the UK regulator has warned against. The Office for Product Safety and Standards (OPSS) issued alert PSA5 in March 2023: those attachments are unsafe and should come off the market. This guide sets out what the alert covers, and what to use if you still want to cut wood with a grinder.

In short

PSA5 says toothed saw blades on angle grinders cause kickback and loss of control, and BS EN 60745-2-3 makes the manual warn you not to fit them. Toothed blades belong on circular saws. For wood on a grinder, look at a toothless carbide grit disc that the maker allows.

The warning in one paragraph

On 14 March 2023, OPSS published Product Safety Alert PSA5. Toothed saw blade attachments sold for angle grinders "increase the risk of kick back and loss of control" and could lead to serious injury or death. BS EN 60745-2-3 requires this line in every grinder manual: "Do not attach a saw chain woodcarving blade or toothed saw blade. Such blades create frequent kickback and loss of control." That sentence is probably already in the booklet in the box.

The legal hook is the Supply of Machinery (Safety) Regulations 2008. Grinders and their interchangeable equipment have to meet essential safety requirements, and the alert says an attachment that raises the risk of kickback cannot meet them. PSA5 followed the 2021 alert PSA2 on chainsaw discs, so both the chain type and the circular-blade type are covered.

PSA5 is a product safety alert, not a new offence for a home user. It asks you to stop using these attachments and asks businesses to take them off sale. Trading Standards, and Environmental Health in Northern Ireland, are asked to act against sellers. Workplace use sits under PUWER, which is a separate duty.

Toothed blade, chainsaw disc, carbide rim

Three kinds of disc turn up in a wood-disc search, and the alert treats them differently.

Toothed saw blade

This looks like a small circular saw blade, often 115 mm or 125 mm, with 24, 40 or 60 carbide teeth and a 22.23 mm bore. It is what PSA5 is about. A circular saw runs at a few thousand rpm behind a riving knife and a sprung lower guard. A 125 mm grinder typically runs at up to around 12,000 rpm, a rule of thumb to check on the tool plate, with a fixed half guard. When a tooth catches a knot or pinches in the kerf, the grinder is pushed back towards you.

Chainsaw carving disc

This is a disc with a short loop of saw chain round the edge, sold for carving. PSA2 covered these in 2021, and PSA5 names them again. They encourage plunge and sculpting cuts, which a grinder was never designed for.

Carbide grit rim

This is a toothless disc with tungsten carbide grit bonded to the edge. It grinds wood away rather than biting it. PSA5 does not mention it. That is a different hazard from a row of teeth, and it is the type most UK buyers use when they want wood cuts on a grinder. It is still only suitable if the grinder maker allows it.

What that means for a 125 mm amazon search

Search amazon.co.uk for a 125 mm wood cutting disc and the results mix all three types. Titles often say "for angle grinder" whichever disc it is. That title is a keyword choice, not a compatibility statement. Look at the photo and the bullets before you add anything to the basket.

If you can see teeth or a chain, and the listing is aimed at a grinder, leave it. If the rim is a continuous grit band, check a 22.23 mm bore, a 125 mm diameter, and a maximum speed at or above the tool's rated rpm. If the speed is missing, find it on the packaging or the maker's page before you use it.

The 125 mm wood cutting disc comparison sorts kept listings by disc type, so you can see which are toothed. The top pick is the Bosch Expert Carbide Multi Wheel 125 mm, a toothless carbide disc with a grit 80 rim and a 22.23 mm bore. At the time of writing it costs £15.96, with 4.7 out of 5 from 1,407 amazon.co.uk reviews. UK reviewers mention laminate, shed parts, fence posts and chipboard on cordless grinders.

The amazon.co.uk listing does not state a maximum speed, and the specification cell says "Plastic" while the bullets describe carbide, so check the disc when it arrives. The bullets say it cuts wood with embedded screws and nails, but a grit disc still kicks if you twist it in the cut. The ranking is explained on the best 125 mm wood cutting disc page.

A 40T blade on a saw that is built for it

None of this means toothed blades are bad. A 40-tooth TCT blade is the normal way to crosscut softwood or sheet material, and it does that better than a grit disc. It belongs on a machine built round it.

A circular saw, plunge saw or mitre saw gives a toothed blade what a grinder cannot: a riving knife so the kerf does not pinch the teeth, a lower guard, a base plate or table, and a blade speed that suits the diameter. The maximum rpm is printed on the blade for that reason.

For lots of straight cuts, a grinder is the wrong tool even with a grit disc: the edge is rough and burnt, and the cut is slow. Match a circular saw blade in the 165 x 20 mm saw blade comparison or the 250 x 30 mm circular saw blade comparison. For aluminium, see the circular saw blade for aluminium comparison.

A grinder spindle takes 22.23 mm. Many 165 mm saws use 20 mm, and larger saws use 30 mm. A reducing ring can make a saw blade fit a saw. It never makes a saw blade suitable for a grinder.

If you already own one

If a toothed blade or chain disc for a grinder is already in the toolbox, stop using it and dispose of it safely. Wrap the teeth before it goes in the bin, or ask the local recycling centre where metal tools should go.

You may get your money back. If the attachment was marketed for an angle grinder, PSA5 says you may be entitled to redress, so contact the seller. The Consumer Rights Act 2015 requires satisfactory quality and fitness for purpose. Keep the order confirmation and a screenshot of the title.

If the listing is still live, report it on amazon.co.uk and to Trading Standards through the Citizens Advice consumer service. PSA5 asks businesses to remove these attachments and to warn buyers. A refund for one blade does not make the next toothed grinder blade acceptable.

What this article will not tell you to do

You will not find fitting steps here for a toothed blade or chain disc on a grinder. The standard and the alert do not recognise a safe way to do it. Holding the tool firmly, or taking shallow passes, does not change kickback. A tooth that catches at 10,000 rpm or more moves faster than you can react.

A carbide grit disc is a different hazard, and PSA5 does not name it. Use only attachment types the grinder maker recommends. Some list carbide wood discs and some do not. If the manual does not mention wood, ask the manufacturer before you rely on a seller's title.

Whichever disc you keep, leave the guard on between you and the disc, use the side handle with both hands on the tool, and clamp the work. Stand to one side of the line. Wear eye protection, hearing protection and a dust mask: wood dust from a grit rim is fine and goes everywhere.

We compared amazon.co.uk listings and public UK sources, including the OPSS alerts. We did not run a lab test. Links to amazon.co.uk may earn us a commission on a qualifying purchase, at no extra cost to you.