Centrolock Carbide Reversible Planer Knife — Double-Edged, 60mm to 650mm

Oak, teak, abrasive hardwood and composite panel stock are what solid tungsten carbide is built to outlast. Carbide holds a working edge through volumes no steel grade reaches, which is what makes the higher price per knife economic on long production runs, where a changeover costs more in stopped machine time than the tooling does. The trade is brittleness: carbide chips where high-speed steel would simply dull, so grit, embedded metal and dirty reclaimed stock will end a set early — take the cleaning pass on HSS and change over. Leitz grinds these to the same 16 x 3 mm section as the steel grade, with a serrated back that locates positively in the head and a cutting edge on both faces, so every knife carries two full lives before replacement. The Type 530 head clamps by centrifugal force through a quick-action gib and two lateral screws, so a change is a wrench job of minutes with no jointing, no setting gauges and no regrinding. Stocked from 60mm to 650mm for Z2 and Z4 heads. On softwood, HSS gives a keener finish at roughly a seventh of the cost.