Troubleshooting - Jet GHD-20 Operator's Manual

Troubleshooting
14
Problem
Probable Cause Solution
Excessive vibration
Motor out-of-balance.
Balance motor or replace.
Reduce feed rate.
Over feeding.
Dull drill bit.
Sharpen drill bit.
Motor stalls
Replace or repair motor.
Motor not running up to
Check fuses in all three legs
speed.
on three Nhase motors ana
replace, . necessary.
Improper quill adjustment.
Adjust quill.
Noisy operation
Noisy spindle.
Lubricate spindle.
Noisy motor.
Check motor bearings or for a
loose motor fan.
Excessive speed.
Reduce speed.
Dull tool.
Sharpen tool or replace.
Drill or tool heats up or burns
Feed rate too slow.
Increase feed enough to clear
work.
chips.
Rotation of drill incorrect.
Reverse motor rotation.
Failure to use cutting oil or
Use cutting oil or coolant (on
coolant (on steel).
steel).
!
No drill spot.
Center punch or center drill
workpiece.
Cutting lips on drill off center.
Regrind drill.
Drill leads off.
Quill loose in head.
Tighten quill.
Bearing play.
Reseat or replace bearings.
Bent drill.
Replace drill.
Excessive drill runout or
Bearing play.
Reseat or replace bearings.
wobble.
Drill not seated properly in the Loosen, reset, and tighten
chuck.
chuck.
Work or fixture comes loose
Failure to clamp work piece or
Clamp workpiece or work
I or spins. work holding device to table.
hold!ng device to the table
I
service.