Page 123 - HOLE MAKING CATALOG p185-310
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Typical Gundrill Applications - USER GUIDE GUNDRILLS
Main Drilling Methods
Typical Gundrill Applications -
Guide Barrel Chip Evacuation and Coolant Flow
Figure 1
Pre-Drilled Guide Hole Figure 3
Boring with chip evacuation and coolant
flowing opposite the boring direction
Figure 2 Figure 4
User Guide Drilling of solid material with chip evacuation and
coolant flow opposite the drilling direction
The gundrill is not a self-centering tool. Therefore, an external
means must be used to guide it to the point of entry into the
workpiece. It is recommended that the machine tool be equipped
with a means for guiding the gundrill, preferably during the entire
drilling process.
An alternative method is a pre-drilled guide hole (figure 2), which
is common for machining centers. Once the drill has been fully
engaged into this hole, it continues to be self-guided.
The guide pads contribute to the high degree of
calibration and provide burnishing of the drilled hole.
Figure 5
Boring with chip evacuation in the boring direction
Figure 6
Boring with a staged tool chip evacuation and
coolant flow in the boring direction
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