Intermittent drill

Illustration of Intermittent drill

Intermittent drilling has two margins that allow the drill to get better SUPPORT AGAINST the drilled hole walls.

Compared to standard twist drills with only one margin, the intermittent drills provide better tolerances, however at the expense of increased cutting resistance due to increased frictional force.
 
The name of the drill comes from the fact that it is suitable for drilling through PRE DRILLED HOLES with higher precision. At the same time, this reduces the risk of tool failure in these cases.

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