Countersunk (CSK) and counterdrilled holes (CDRILL) are two holes drilled
at different depths that share a common center. For countersunk holes,
specify the diameter and the included angle of the countersink.
There is no
depth to the larger hole since it only creates a bevel at the opening of the
smaller hole. For counterdrilled holes, specify the diameter and the depth of
the counterdrill. The larger diameter hole automatically creates a bevel
determined by the angle of the drill bit; therefore, specifying the included
angle of the counterdrill is optional.
The depth dimension is the depth of the
full diameter of the counterdrill from the outer surface of the part.
Figure 3-33 shows the dimensioning of countersunk and counterdrilled holes.
Figure 3-33.Dimensioning countersunk and
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