GRAFF professional drill bit for stainless steel 4 mm from high-speed steel P6M5K5. These drill bits have accuracy class A1 thanks to their polished cutting edge.
A sharpening angle of cutting edge at the apex is 135 degrees. It provides ideal chip removal and, as a result, lower heating of the drill tip. Cross-shaped undercut of cutting edges at the apex allows to start drilling without predrilling with a centering drill or punching. Standard size drill bits are made according to DIN 338. They are equally suitable for industry, small workshops and households.
Drill size: – 4x43x75 mm where 4 mm is diameter, 43 mm is working length and 75 mm is total length.
A recommended operating speed for a drill bit with 4 mm diameter is 1435 RPM. Please note that this speed is specified for stainless steel. When processing other types of metal, speed differs.