12.1 · Machine Troubleshooting
Machine Troubleshooting Guide
When a machine acts up, don't start replacing parts. Work the problem systematically: observe the symptom, list possible causes, check the easy things first, then dig deeper.
Structured Method
Symptom → What exactly is happening?
Possible Causes → What could cause this?
Diagnostic Checks → What can I measure?
Corrective Action → What fixes it?
Prevention → How do we stop it recurring?
Common Problems
| Symptom | Common causes | First check |
|---|---|---|
| Poor surface finish / chatter | Tool wear, deflection, loose fixturing, spindle bearing | Is the tool sharp? Is the part rigid? |
| Dimensional drift | Thermal growth, worn ballscrew, lube issue | Did the machine warm up? Check after 30 min. |
| Alarm on axis move | Overtravel, servo fault, encoder error | Read the alarm code — don't just reset |
| Tool changer failure | Air pressure low, misaligned pot, jammed chip | Air pressure? Any chip in the drum? |
| Chuck not holding | Clamp pressure low, worn jaws, hydraulic leak | Gauge the chuck pressure |
Start with the obvious. 80% of "machine problems" are low air pressure, empty lube tank, a chip jam, or a dull tool. Check these before calling a technician. Read the alarm code — controllers tell you exactly what's wrong if you look.