How to fit a 165mm circular saw blade
Updated: October 2026
The new 165 mm blade is on the bench and you want the next cut to track instead of burning a brown line down softwood. Fitting is direction, a bore that is actually tight, and a saw that cannot start while your fingers are on the flange. This is how to fit a 165mm circular saw blade: battery or plug isolated, arrows matched, a 16 mm ring only if the arbor is smaller than 20 mm, then a scrap cut before the worktop. Listings sit on the [main comparison](/hub/saw-accessories/saw-blade-165x20). Follow the saw in your hands.
The new 165 mm blade is on the bench and you want the next cut to track instead of burning a brown line down softwood.
The new 165 mm blade is on the bench and you want the next cut to track instead of burning a brown line down softwood. Fitting is direction, a bore that is actually tight, and a saw that cannot start while your fingers are on the flange. This is how to fit a 165mm circular saw blade: battery or plug isolated, arrows matched, a 16 mm ring only if the arbor is smaller than 20 mm, then a scrap cut before the worktop. Listings sit on the main comparison. Follow the saw in your hands.
Our top picks
| Badge | Product | 16 mm ring | Arbor it suits | Stated kerf | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  DeWalt DeWalt 24T framing blade | Not listed | 20 mm, or a ring you already own | Thin, no millimetre | 6.7 | about £11.55 | View offer |
 Saxton Saxton 80T fine blade | In the bullet and the components line | 20 mm, or 16 mm with that ring | 2.0 mm, plate 1.4 mm | 9.2 | about £13.99 | View offer | |
| Best value |  Saxton Saxton 60T wood blade | In the bullet and the components line | 20 mm, or 16 mm with that ring | 2.0 mm, plate 1.4 mm | 9.0 | about £11.99 | View offer |
On this page
Make the saw dead
Take the battery off a cordless saw, or pull the plug on a corded one, before the guard comes back. Kougar’s UK hire sheet says to switch off and remove the battery before a blade change. Bosch’s GKS 18V-57-2 manual puts the same idea as before any work. A spindle lock is for a shaft that has already stopped. Pressing it while the blade is still spinning is how the lock pin gets sheared.
Hold the lower guard back only after the pack is off the rail. If the guard, riving knife, or flange is missing, stop. PUWER 1998 expects work equipment to be suitable and maintained.
Match the arrows
The arrow on the blade matches the arrow on the guard or the housing. On a handheld circular saw the teeth cut upward at the front, so the tips at the nose of the shoe point up toward the guard. That upstroke is why the show face is usually against the shoe, decorative side down, when chipping matters. Blade-left saws often hide the printed face once the blade is the right way round.
One stored UK review of a HARDWIN blade on a Bosch GKS 18V-Li had the print on the side the buyer thought was wrong, and the cut was still clean. One UK review of the DeWalt 40-tooth blade, sold as B00DI8RF0Y, burned the wood until the blade was turned over. If your manual draws the arrow the other way for a plunge saw, the manual wins.
Seat the ring only if the arbor is smaller
A 20 mm bore belongs on a 20 mm arbor with no bush. Add a 16 mm reducing ring only when the shaft is 16 mm. The ring has to sit flush, and it must not be thicker than the plate, or the flanges pinch the bush and the disc rattles. Selco’s DART ring page tells you to press or glue the ring in place, and not to use one if the flange is less than 5 mm larger than the original bore.
DeWalt’s singles in this set do not list a ring. Saxton’s bullets do. If the bag has no ring and the arbor is 16 mm, stop and get the ring. A loose 20 mm hole on a 16 mm shaft will wander off centre. There is no ring to fit when the arbor is already 20 mm.
Flanges, bolt, and the guard
Clean flanges go back in the order your manual shows, usually dished faces toward the blade so the clamp is at the rim. Bosch’s GKS 18V-57-2 manual gives 6 to 9 Nm, which it describes as hand-tight plus about a quarter turn. That is Bosch’s figure for that saw. Do not copy 6 to 9 Nm onto a DeWalt, a Makita, or a no-name plunge saw. If the manual says firm with the spanner supplied, use that spanner.
Let the lower guard go and watch it snap shut. A guard that stays open is a reason to stop. The riving knife, if your saw has one, should sit in the kerf. Health and Safety Executive bench-saw gaps, including an 8 mm knife gap, are for a table saw. They are not this procedure. Fit a scrap and listen. A brown burn or a wobble means the blade comes off again before the kitchen board does.
Common questions
Do I take the battery out first?
Yes. Remove the battery, or unplug a corded saw, before you retract the guard or touch the bolt. The spindle lock is only for a shaft that has stopped. Kougar’s hire sheet and the Bosch cordless manual both start from an isolated saw.
Which way do the teeth face?
On a handheld circular saw the teeth at the front of the shoe point upward, and the arrow on the blade matches the arrow on the guard. Tear-out shows on the top face unless you put the show face down. One DeWalt 40-tooth review only ran cleanly after the blade was flipped.
What if the label is hidden?
Match the arrows and the tooth direction. One HARDWIN buyer on a Bosch GKS 18V-Li had the label on the side they thought was wrong while the cut stayed clean. If you cannot find an arrow, do not guess from the logo. Use the manual for that saw.
How does the 16 mm ring go in?
Press or glue it into the 20 mm hole so it is flush, and only if the arbor is 16 mm. The ring must not stand proud of the plate. The flanges need to be at least 5 mm larger than the original bore. No ring goes on a 20 mm arbor.
How tight is the bolt?
Tight enough that the blade cannot slip, using the spanner that came with the saw. Bosch quotes 6 to 9 Nm on the GKS 18V-57-2, hand-tight plus a quarter turn. That number is not a universal torque for every 165 mm saw sold in the UK.
When do I stop and get a professional?
Stop if the lower guard does not spring shut, if the riving knife is bent or missing, or if the flanges are damaged. Also stop if you are about to cut a post-formed worktop you cannot afford to scrap and you are not sure of the face. Repairing a saw that will not guard itself is not a DIY job.
Related pages
Sources
Sources from the research digest. amazon.co.uk prices, stars, and review counts are the listing lines captured on 15 October 2026.
- amazon.co.uk listings for these 165 x 20 mm blades, 15 October 2026 (retrieved 15 October 2026)
- HSE WIS16, circular saw benches (retrieved 15 October 2026)
- HSE, circular rip saws (retrieved 15 October 2026)
- Provision and Use of Work Equipment Regulations 1998 (retrieved 15 October 2026)
- BS EN 847-1:2017, marking of circular saw blades (retrieved 15 October 2026)
- Compel, circular saw blade size chart (retrieved 15 October 2026)
- Saxton, TCT reduction rings (retrieved 15 October 2026)
- Selco, DART reducing ring 20 mm to 16 mm (retrieved 15 October 2026)