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How to use a Bosch mitre saw

Updated: 21 October 2026

The saw is on the bench, the skirting is in the hall, and the first cut feels urgent. How to use a Bosch mitre saw, for any of the six Professional listings in the [Bosch Professional mitre saw comparison](/hub/power-saws/bosch-professional-mitre-saw), starts before the plug. UK reviews of these GCM models go wrong on square, on the space behind the rails, on support and on dust. This page is the setup, not a price table. Peter F. compared amazon.co.uk reviews and public UK guidance. There was no lab test. A qualifying purchase can earn a commission at no extra cost to you.

The saw is on the bench, the skirting is in the hall, and the first cut feels urgent.

Our top picks

Bosch Bosch GCM305-216S

Best overall

Bosch Bosch GCM305-216S
6.9/10about £209.49
View offer
Bosch Bosch GCM 800 SJ

Rank 2

Bosch Bosch GCM 800 SJ
7.8/10about £229.80
View offer
Bosch Bosch GCM 305-254 D

Rank 3

Bosch Bosch GCM 305-254 D
6.4/10about £627.87
View offer
On this page
  1. 1.Fix the saw before you plug it in
  2. 2.Prove 0 and 45 on scrap
  3. 3.Dust and noise while you cut
  4. 4.When to stop

Fix the saw before you plug it in

Give the rails somewhere to go. GCM 80 SJ and GCM 305-254 D reviews both say the slide needs space behind the bench. Pull the head back with the saw isolated and mark where the bars end. A saw against the wall will not deliver the 270 mm claim. Bolt the feet before you trust an angle. The GCM305-216S amazon weight cell says 20.4 kg and Bosch lists 15.3 kg, so do not argue from the cell. Support the timber past the fence. The D models include supports. The GCM 800 SJ title does not. Which saw to buy stays on the buying guide.

Prove 0 and 45 on scrap

Do not trust the detent because it clicked. On the GCM 800 SJ, UK reviews found the 45 degree stops accurate, and one reviewer measured about 87 degrees at the 90 degree stop. Set a square against the fence and the isolated blade. Cut a scrap of the same profile and dry-fit the pair. The fence sets the mitre, not the laser. An LED line on the GCM305-216S shows where this blade will land. It does not repair a stop that is out. The GCM 800 SJ bullets do not include a depth stop, and one reviewer improvised an M5 nut. That nut is not a Bosch part to copy.
Bosch Bosch GCM305-216S

Testsieger

Bosch Bosch GCM305-216S
6.9/10about £209.49
View offer

Dust and noise while you cut

Extraction is the control. The bag is the leftover. The GCM305-216S includes a dust bag, and UK reviews still want a vacuum indoors. The GCM 800 SJ title does not list a bag. A UK review of the GCM 18V-254 D calls the dust path poor. A bag is not an M-class extractor, and a household vacuum with a HEPA filter is not one either. The Health and Safety Executive expects M-class or H-class extraction for wood dust at work, and FFP3 when indoor trigger time reaches about 15–30 minutes. This set has no measured decibel figure. HSE treats 85 dB(A) as the normal upper action value, so ear defenders for a morning of skirting are a reasonable precaution. Packs and leads are on cordless or corded.

When to stop

Return a saw that will not set. On the GCM 305-254 D, a UK reviewer found the bevel detent jammed on arrival. On the GCM 18V-254 D, a trigger lit the laser and did not start the blade. That is a fault, not a setup step. Stop when the profile is historic or listed, when the site is 110 V and these titles are 240 V class, or when employees are cutting with no extraction plan. The GCM 18V-254 D blade is named Standard for Wood. Believe the blade name, not a surface cell that says metal. Let the blade stop before you lift the head. An internal corner still wants a scribe, on skirting and architrave.

Common questions

How do I know the 0 degree stop is square?
Put a square on the fence and the isolated blade, then cut a scrap and dry-fit two pieces. On the GCM 800 SJ, one UK reviewer measured about 87 degrees at the 90 degree stop. A click from the detent is not the check.
How much room do the rails need?
Enough for the full pull, which you find by drawing the head back while the saw is isolated. GCM 80 SJ and GCM 305-254 D reviews both say the bars need space behind the bench. A saw against the wall will not deliver the horizontal capacity in the bullets.
Is the dust bag enough in a garage?
Not for a long indoor session. GCM305-216S reviewers still wanted a vacuum, and one GCM 18V-254 D review calls the dust path poor. At work, HSE expects M-class or H-class extraction. A few test cuts are a different job from a landing.
Do I need ear defenders if I only cut skirting?
There is no decibel figure for these six models. HSE treats 85 dB(A) as the normal upper action value for woodworking. A morning of mitres is enough time to wear defenders in a small garage.
Can I trench-cut on the GCM 800 SJ?
The listing does not include a depth stop, and UK reviewers disagree. One improvised an M5 nut. That is not a Bosch part to copy. For repeat lap joints, use a saw that states a depth stop.
What do I do if the bevel detent is jammed?
Stop. A UK review of the GCM 305-254 D describes a detent jammed on arrival. Return it rather than forcing the lever. Do the same if a GCM 18V-254 D trigger lights a laser and does not start the blade.
When should I stop and call a joiner?
When the profile is historic or listed, when the site is 110 V only, when the saw arrives unable to square or to start, or when people are cutting all day with no extraction plan. A modern torus you can patch is still a job you can set up with a square and a scrap.

Related pages

Best Bosch Professional mitre saw

Bosch professional mitre saw

Bosch Professional mitre saw buying guide: capacity

Cordless or corded Bosch Professional mitre saw UK

How to cut skirting with a Bosch Professional mitre saw

Sources

Public UK sources, Bosch GB product pages and the amazon.co.uk listings compared on this page. Bosch GB shelf prices are for 19 October 2026 and are not the amazon column.

  1. HSE: Wood dust (retrieved October 2026)
  2. HSE: Cutting and sanding wood (retrieved October 2026)
  3. HSE: PUWER overview (retrieved October 2026)
  4. HSE: Noise for employers (retrieved October 2026)
  5. Bosch GCM305-216S (retrieved October 2026)
  6. Bosch GCM 800 SJ (retrieved October 2026)
  7. Bosch GCM 305-254 D (retrieved October 2026)
  8. Bosch GCM 18V-254 D (retrieved October 2026)