130° 110°
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Integral drill steel are grouped in
series. When drilling a deep hole
start with a short, wide drill and
continue successively using the
next size down. This avoids jam-
ming and allows easy extraction.
To get maximum effect, tools should be kept sharp and
their shanks must have the correct lengths. This length
should be checked with the shank template.
On drilling tools, blow through the air-flushing channel to
check that it is not blocked.
The standard cutting edge angle is 110°. For better re-
sults in loose rock it can be reground to 130°.