Technical information - Point cuts

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 possible. Disadvantages:
broad cutting edge requires considerable pressure.

» Helical point normal ground

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.

» Ground for grey cast iron in accordance with DIN 1412 D

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 as less pressure is required.
Disadvantages:
additional regrinding work.

» Cut chisel edge in accordance with DIN 1412 A

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-sided loading. Can only be ground to perfection by machine.

» Centre point in accordance with DIN 1412 E

Applications:
for drills with very strong cores, for particularly tough, hard materials and for deep-hole drills. Advantages:
good centring, little pressure required. Chip distribution improves chip removal.
Disadvantages:
perfect grinding only possible by machine.

» Split point in accordance with DIN 1412 C

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 values are employed. Concave cutting produces short metal chips.
Disadvantages:
extra work involved in regrinding.

» Helical point with secondary free tool flank and point

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-sided load and lateral forces. Does not catch in thin work pieces. Disadvantages:
high pressure required, tendency to slip, extra work involved in regrinding.

» Cut chisel edge with corrected major cutting edge in accordance with DIN 1412 B