- Troubleshooting Guide

Problem	Possible Causes
Corners Break Down	Cutting speed too high Hard spots in material Insufficient coolant at drill point Flutes clogged with chips
Cutting lips chip	Too much feed Lip relief too great
Margin Chips	Oversize drill bushing
Drill breaks	Point improperly ground Too much feed Drill is dull Flutes are clogged with chips
Tang breaks	Imperfect fit between taper shank and socket typically caused by dirt or chips. Socket is badly worn.
Drill splits up center	Not enough lip relief Too much feed
Drill will not enter work	Drill is dull Not enough lip relief Web is too heavy
Surface of hole is rough	Point improperly ground or dull Insuffient coolant at drill point Too much feed Workholding device is not rigid
Hole is oversize	Unequal point angles Unequal length of cutting edges Machine spindle bearings may be worn
Chip shape changes while drilling	Drill is dull Cutting lips are chipped
Large chip coming out of one flute, small chip coming out of the other	Point is improperly ground and one lip is doing all of the cutting.