Short drilling up to 3 x d with additional 90° chamfer

Pilot drilling and short drilling 

The solid carbide drill bit CrazyDrill Coolpilot (pilot respectively short drill and countersink drill bit) represents a well-coordinated program with the deep hole drill CrazyDrill Cool SST-Inox. The base for precise drilling and stable machining is provided by the pilot drilling with CrazyDrill Coolpilot or, on inclined surfaces by CrazyDrill Crosspilot. The pilot drill ensures a high position accuracy due to its short and sturdy construction. The pilot hole is the guidance for the subsequent drill to guide it cylindrically and guarantee the straightness and perpendicularity of the deep hole.

The quality of the drilling (no measurable transition from pilot hole size to follow-up deep hole size) as well as the stable machining process (no jamming) are guaranteed by means of a predetermined tool tolerance.

Realizing fast and easily short bore holes? CrazyDrill Coolpilot is also a perfect solution for accurate and quick drilling of short holes up to a drilling depth of 3 x d with 90° chamfer. 

Tolerance of pilot drill CrazyDrill Coolpilot (m5):
≤ 3 mm (.118”): + 0.002 mm /+ 0.006 mm (+.00008” /+ .00024”)
≤ 6.35 mm (.250”): + 0.004 mm /+ 0.009 mm (+.00016” /+ .0004”) 

Tolerance of pilot drill CrazyDrill Crosspilot (inclined surfaces) (k6):
≤ 3 mm (.118”): + 0 mm /+ 0.006 mm (+ 0” /+ .00024”)
≤ 6.35 mm (.250”): + 0.001 mm /+ 0.009 mm (+ .00004” /+ .0004”) 

Tolerance of follow-up drill CrazyDrill Cool SST-Inox (k5):
≤ 3 mm (.118”): + 0 mm /+ 0.004 mm (+ 0” /+ 00016”)
≤ 6.35 mm (.250”): + 0.001 mm /+ 0.006 mm (+ .00004” /+ .00024”)

Drilling process

General information

In the industry of metal work tools, shorter processing times are always in high demand. At the same time, the requirements to the manufacturing precision and the process reliability are extremely high. In order to fulfill these requirements, the "machine tool – spindle – tool – tool holder" system need to be considered as a whole (see additional info).

For the use of the CrazyDrill Coolpilot, Mikron Tool has defined a fast and reliable procedure which achieves optimal drilling results.

Quick short drilling up to 3 x d and 90° chamfer or pilot drilling

  1. Pilot drilling or short drilling up to 3 x d in one step

Drilling up to 3 x d with CrazyDrill Coolpilot in one step (see cutting data chart)

1. CrazyDrill Coolpilot:

  • Activate internal cooling
  • Drilling in one step with recommended cutting speed and feed rate (see cutting data table)


  • If needed, after the desired cutting depth of 3 x d is reached, a chamfer angle of 90° can be realized



After the drill reached desired cutting depth, return at increased feed rate (or in case of perfect conditions rapid traverse) to safety position.

Tested and approved

Mikron Tool has determined the ideal cutting parameters (drilling speed to tool life ratio and process reliability) when using CrazyDrill Coolpilot. These are listed in the cutting data tables according to drill diameter, drilling depth and material to be machined. The detailed cutting data tested by Mikron Tool, such as cutting speed vc, feed rate f and drilling impact Q, permit a quick and secure machining.

The overview of the cutting values table according to material group, material type, hardness degree and tensile strength, material number, DIN and AISI/ASTM/UNS permits quick determination of the parameters to be used.


An impact-resistant and user-friendly drill packaging is absolutely necessary for CrazyDrill Coolpilot. Mikron Tool offers all tools of the CrazyDrill Coolpilot family in a high quality, single package.

Notes or further questions

Please find more information about tool holders, cooling or lubrication under “Additional Info”.

Mikron Tool has an international team of cutting technology experts who are pleased to answer your questions (how to use a drill, tools, machines, tool holders, cooling, machining process…).

Use this link to contact us directly.