How long do circular saw blades last?

Signs a blade is dull

A dull blade makes you push harder, and cuts slow down. Look for burn marks on the cut edge, more splintering on the face of sheet goods, a louder or labouring motor and the saw drifting off line. On a cordless saw, you will get noticeably fewer cuts per battery charge.

Inspect the teeth in good light. Rounded tips, chips, missing teeth or a dull shine on the carbide all show wear. A missing or cracked tooth means replace the blade at once.

Cleaning a blade

Resin and pitch from softwood and treated timber build up on the teeth and body, making the blade run hot. Clean it before deciding it is dull.

1. 1

   Disconnect power and remove the blade, following the saw's manual.

2. 2

   Soak the blade in a blade cleaning solution or warm soapy water for a few minutes.

3. 3

   Scrub the teeth and body with a soft nylon brush, not a wire brush.

4. 4

   Rinse, dry thoroughly and wipe with a light protective oil if you will store it.

5. 5

   Refit the blade with the teeth pointing in the right direction.

Note:Wear cut resistant gloves when handling blades. Never clean a blade while it is fitted to a connected saw.

Can you sharpen circular saw blades?

Yes. Tungsten carbide tipped blades are sharpened on diamond wheels by saw sharpening services, often called saw doctors. A good blade can usually be resharpened several times, until the carbide tips get too small. They can also replace damaged teeth on some blades.

Home sharpening of carbide teeth is difficult to do accurately. Cheap thin kerf blades sold in multi packs are often not worth sending away; replacing them is simpler. Premium blades for mitre saws and plunge saws usually are worth sharpening.

What shortens blade life

Cutting the wrong material is the biggest cause. Nails, screws and grit in reclaimed timber chip carbide teeth. Laminates, MDF and chipboard contain resins and glues that wear teeth faster than solid softwood. Forcing the saw, using a rip blade for fine crosscuts and letting resin build up all add wear.

Storing blades loose in a toolbox where teeth knock together also chips them. Keep blades in their sleeves or a blade case.

• Use the right blade for the material.
• Check reclaimed timber for nails.
• Keep blades clean.
• Store them so teeth cannot touch.

Choosing the right blade

Fewer teeth cut faster and suit ripping; more teeth give a cleaner finish for crosscuts and sheet goods. Specialist blades exist for laminate, aluminium and fibre cement. Check the diameter, bore and maximum speed match your saw. See mitre and circular saw blades explained and how to change a mitre saw blade.

Blade sizes are covered in what size circular saw do you need.

See circular saws →

Blade care and safety

A sharp blade is safer as well as faster. Dull blades need more force and are more likely to bind and kick back; see circular saw kickback. If a cut starts burning, stop and check the blade before carrying on.

For binding and burning specifically, read circular saw binding and burning.

Frequently asked questions

How long does a circular saw blade last? It depends on use and material. Occasional DIY use can keep a quality blade sharp for years; heavy site use wears one far faster.

Is it worth sharpening a circular saw blade? For quality TCT blades, usually yes. For cheap thin blades, replacement is often simpler.

How do I clean resin off a saw blade? Soak it in blade cleaner or warm soapy water and scrub with a soft nylon brush.

Can a dull blade cause kickback? Yes. It needs more force and is more likely to bind.