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Deep hole drilling

Requirement deep hole drilling

For good hole drilling results, cooling, lubrication and high-pressure coolant systems are required. Single flue gundrilling cannot only be achieved on deep drilling machines but is also very good on machining centers (drilling, turning and milling center) with:

  • Deep-hole drilling oil,
  • Emulsion (min. 10 – 12 % concentration, with additives),
  • and under conditions, with a minimum quantity air/lubrication system


Drill guide

The asymmetric goemetry single-edged single flute gundrill is nit self-starting, therefore a pilot hole or drill bushing is required.

The prevent outbreaks during retraction of single flute gundrill we recommend plunging in counterclockwise rotation.

Too big a diameter difference between the tool and drill bush or pilot hole can cause the following problems:

  • poor hole quality
  • excessive hole straightness deviation
  • drill breakage

Drill bush

Recommendation: Bushes DIN 179A medium.

Drill bushing has a form set against the workpiece!

Pilot drilling

Recommendation: pilot drill with m7 tolerance.


Deep drilling machine

Machining center


  • Make a pilot hole
  • Enter with stationary spindle or speed < 50 rpm
  • Set coolant pressure, speed and feed
  • Continuous drilling to depth without peck
  • Switch off coolant supply after reaching hole depth
  • Retraction with stationary spindle or < 50 rpm
Failure to comply may result in tool breakage.

Special nose grinds

In the following examples, various forms are shown:
Please contact us if you need a special grind for your tools.

Cutting parameters

The information below are average values as a guide. They depend on meterial, bore diameter, unsupported tool length, cooling lubricant, drilling conditions ans stability of the machine.

PDF Download

Summary table Typ 100, Typ 110, Typ 120

Feed should be reduced at start, exit and cross holes.