S&S-Shop HM 190 × 30 mm, 40T

Every figure below is a manufacturer specification read off the listing itself. The judgments are ours.

What the specification says

Ø 190 × 30 mm (7.48 × 1.18 in), 40 carbide-tipped teeth, supplied with reducer rings. No part number and no kerf on the listing.

Bore before diameter

The diameter decides whether the blade clears the guard; the bore decides whether it goes onto the shaft at all. Thirty millimeters is the European standard, and reducer rings step a large bore down onto a smaller shaft — never the other way round. A ring that is a loose fit lets the blade run slightly off center, which shows up as vibration and a cut that wanders rather than as an obvious fault.

Read both figures off the machine rather than off the blade you are replacing, which may itself have been the wrong one.

Forty teeth is the middle setting

Forty teeth on a 190 mm (7.48 in) blade is the general-purpose choice: fast enough to break down chipboard and clean enough that the edge does not need planing. The manufacturer names solid timber, chipboard, plastic and cable trunking, which is the honest range for a blade at this tooth count.