Page 665 - Iscar
P. 665
USER GUIDE
GUNDRILLS
When using a gundrill on a lathe machine, a short solid
carbide centering drill should be used prior to the gundrill.
Once the gundrill enters the pre-drilled hole,
it is self-guided.
1
Never try to penetrate the
Drilling a pre-hole
(drill diameter +0.02 mm) workpiece by using a gundrill
2
Gundrill penetration
through the pre-hole A shallow pre-hole can’t lead
the unbalanced gundrill
2 x D min
Drill Penetration Instructions
1 Rotate the drill counterclockwise prior to 2 Stop the drill rotation and start 3 Rotate the drill clockwise
and during hole penetration the coolant prior to drilling operation
The Influence of Tool vs. Workpiece Rotation
Rotating tool Rotating workpiece Rotating tool & workpiece
Worst Medium Best
The maximum misalignment between the drill
bushing and the workpiece center line Rotating Workpiece
should not exceed 0.02 mm (.0008”). Bushing
Stationary Drill
Max.
0.02 mm
.0008"
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