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XYZ Machine Tools Ltd
XYZ Bed Mill Safety, Installation, Maintenance, Service & Parts List Manual
3.0
Troubleshooting by Symptom
Use this section to begin the process of resolving a problem. Each symptom type is described in a few
words and then more fully described in an explanatory paragraph. Following this, is a chart that directs in
the most logical steps.
DANGER!
Some of these checks involve accessing potentially hazardous mechanical or electrical
systems. These checks must only be carried out by competent personnel.
3.1
Problems Relating To Machining Results
3.1.1
Poor Finish
The part finish is marred with scallops or is very rough.
Do the following Service Codes and document values:
Code 33 Software Identification. This is needed if you call Customer Service
Code 11 Measures backlash in the system (Only used on Dual Feedback systems)
Code 12 Feed Forward Constant
Code 127 Measures backlash in the system (not used on Dual Feedback systems)
Code 128 Enter backlash compensation
Possible Cause
Check This
Too much backlash entered for code
128 or calculated with code 11.
Verify nothing is mechanically loose and the backlash values are
not higher than what physically is in the system.
Machine Tool & Setup problem
Check for any looseness in the setup (Tool, Tool holder, Part,
Vice, or Fixture). Check the condition and type of cutter being
used, type of material, RPM and Feedrate, etc. See Machine
Tool & Setup Section 4.1
Table, Saddle, or Ram Locks are
locked
Make sure the Table, Saddle, and Ram Locks are unlocked.
Never use gib locks with a CNC machine.
Inadequate or no Lubrication to
Ballscrews and Way surfaces
Make sure all the Way surfaces are getting proper lubrication. If
not, check to make sure that the lube pump is functioning
properly. Also check for any pinched or blocked oil lines. See
Lubrication Section 4.1.3
X, Y, and Z-axis Gibs are not
adjusted properly
Check the adjustment of the X, Y, and Z-axis Gibs. See X, Y,
and Z-axis Gib Adjustments in Section 5.2.1.
X & Y-axis Drive Trains are loose
Check Repeatability using the Repeatability and Positional
Accuracy procedure. Step by step, carefully inspect the Drive
Train for any looseness. It may be necessary to disassemble
and then reassemble the Drive Train. See Mechanical Drive
Train (X, Y) Section 4.2
Way surfaces are pocked, scarred, or
excessively worn
Visually check the condition of all the Way surfaces. For
machines that may have excessively worn Way surfaces you
may need to adjust the Gibs in this area. This will affect
performance when using the machine outside of this area.
Check lubrication to affected areas.
3.1.2
Circles Out of Round
Circles are not round within 0.05 mm TIR over 75 mm DIA. This is best measured by placing a dial
indicator in the quill and sweeping around the part.
Note: The typical slideway-milling machine is not capable of achieving more precise results. If more
precise circles are required, then it is recommended to use a precision boring head/boring bar.