| Step drill bits Size: 6-60mm (12 steps:6,10,15,20,25,30,35,40,45,50,55,60mm). Shank diameter: 13 mm. Step drill Material: HSS 4241 Application: The step suitable for workpieces with hardness below 25, such as carbon steel, sheet metal, insulation board, PVC board, board and wood. The thickness of the part under 5mm. Note: Use water cooling in the drill to extend the life of the bit. Recommended drilling speed 250-400 rpm. Spiral Groove Slot: 135 Split point tip and dual flute design for self-centering and deburring, spiral groove helps eliminate chips while drilling. | |