A mitre saw with a tired blade is the single most misdiagnosed tool we see. People describe a saw that “strains”, leaves burn marks, or no longer cuts square — and almost every time the saw itself is fine. A new TCT saw blade in the right tooth count restores it to factory performance for a fraction of the cost of a new saw.
The signs are familiar. Burning along the cut edge, especially on softwoods, is friction from a dull tooth. A blade that pulls to one side has heat-distorted teeth or chipped carbide. Cuts that are no longer square at 90° are often the blade flexing rather than the saw being out of calibration. And anything described as “smoke at the cut” is a blade that should have been changed two cuts ago.
Tooth count matters more than brand. A general-purpose 254mm mitre saw blade in 40 to 48 teeth is the workhorse for site joinery. For a glass-smooth crosscut on hardwood, oak skirting or finished trim, 60 to 80 teeth gives the cleaner finish. For aluminium and non-ferrous, look for a triple-chip-grind blade rated for non-ferrous work — a wood blade will throw teeth on aluminium. Negative-hook geometry on sliding mitres is non-negotiable; positive hook on a sliding head will try to climb the workpiece.
Bore size on UK mitre saws is almost always 30mm with a reducer ring to 25.4mm or 16mm for older or imported saws. Check the saw spec before ordering and keep the original reducer if there is one. Blade thickness matters too — a thinner kerf cuts faster and burns less, but flexes more in deep crosscuts.
While the blade is off, check the brushes. A saw that has been running on a tired blade has been working the motor harder than it should, and tired brushes are common as a follow-on. Direct fitments are under DeWalt mitre saw carbon brushes, Makita mitre saw brushes and the wider carbon brush range. For the rest of the wear parts on a saw — belts, bearings and switches — the tool parts hub is the fastest route.