RUKO Catalogue

01 15 N E U C D A B Point cuts in accordance with DIN 1412 Other point cuts Shape N: Helical point normal ground Applications: for all normal drilling work in steel, non-ferrous metal and plastic. The point angles depend on the ease with which the materials can be cut. Advantages: powerful main cut, resistant to impact and lateral forces. Simple manual grinding possi- ble. Disadvantages: broad cutting edge requires considerable pressure. Shape A: Cut chisel edge Applications: for all normal drilling work using drills with a strong core, for drilling into solid materials with larger drill diameters. Advantages: good centring when starting to drill, as the length of the chisel edge is reduced to 1/10 of the drill diameter, and fewer pressure is required. Disadvantages: additional regrinding work. Shape B: Cut chisel edge with corrected major cutting edge Applications: for drilling high-density steel, for manganese steel with over 10 % Mn, for hard spring steel and for drilling out. Advantages: resistant to impact, one-way load and lateral forces. Does not catch in thin workpieces. Disadvantages: high pressure required, tendency to slip, extra work involved in regrinding. Shape C: Split point Applications: for drills with very strong cores, for particularly tough, hard materials and for deep-hole drills. Advantages: good centring, little pressure required. Chip spreading improves chip removal. Disadvantages: perfect grinding only possible by machine. Shape D: Ground for grey cast iron Applications: for drilling grey cast iron, malleable cast iron and forgings. Advantages: wear on cutting corners is reduced by extended major cutting edges, resistant to impact, good heat conductivity, all giving improved tool life. Disadvantages: extra work involved in regrinding. Shape E: Centre point Applications: for drilling sheet-metal and soft materials, for blind holes with flat bottoms. Advantages: good centring, minimal formation of burrs when through-drilling, precise drilling in thin sheets and pipes, does not catch. Available in diameters of 2.5 mm upwards. Disadvantages: sensitive to impact and one-way loading. Can only be ground to perfection by machine. Shape U: Special ground Applications: for drills with sturdy profiles suitable for use in automated processing, with narrow grooves and strong cores. Advantages: extremely good self-centring behaviour when maximum cutting valuminiumes are employed. Concave cutting produces short metal chips. Disadvantages: extra work involved in regrinding.