A CNC router is a powerful tool, but like any machine, it can experience issues during operation. Below are some of the most common CNC router problems and their solutions, helping you troubleshoot efficiently and keep your machine running smoothly.
1. Tool Breakage When Engraving Hard Materials
Problem:
The cutting tool frequently breaks when processing harder materials.
Possible Causes & Solutions:
✅ Use the correct cutting parameters and tool selection based on the material type.
✅ Apply appropriate lubricants to reduce friction and heat buildup.
2. Engraving Machine Cannot Start at the Correct Origin
Problem:
The CNC router does not engrave at the expected starting point.
Possible Causes & Solutions:
✅ Ensure that the layout size of the design file matches the machine settings.
✅ Check if there is an offset (OFFSET) applied in the software and correct it if necessary.
3. Spindle Motor Suddenly Stops or Rotates Slowly
Problem:
During operation, the spindle motor slows down or stops unexpectedly.
Possible Causes & Solutions:
✅ If the working voltage is unstable or overloaded, install a voltage stabilizer.
✅ Check the wiring connections, ensuring there are no loose or unsoldered wires.
4. CNC Router Origin Shifts During Operation
Problem:
After setting the origin, the machine sometimes moves unexpectedly forward or to the right.
Possible Causes & Solutions:
✅ The limit switch might be faulty—replace it if needed.
✅ If the driveline is loose, tighten it securely.
5. X, Y, Z Axis Positions Are Not Fixed After Resetting
Problem:
When resetting the CNC router, the axis positions vary unexpectedly.
Possible Causes & Solutions:
✅ Replace a faulty limit switch.
✅ Check if the driveline is broken and replace it if necessary.
✅ If the driver board is damaged, replace it.
6. Engraving Lines Appear Wider Than Expected
Problem:
The CNC router produces engraving lines that are too wide.
Possible Causes & Solutions:
✅ Adjust the focal length of the laser or focusing tube.
✅ Correctly adjust the current settings for precise engraving.
7. CNC Router Cannot Transmit Signals to the Computer
Problem:
The computer and CNC machine fail to communicate.
Possible Causes & Solutions:
✅ Check if the software parameters are set correctly.
✅ Ensure the machine is properly connected to the computer.
✅ Test another computer serial port if the current one is faulty.
✅ Match the baud rate settings of the software and machine.
8. Error Message: "Card Failed to Open"
Problem:
The computer prompts an error when opening the CNC software.
Possible Causes & Solutions:
✅ Check if the driver for the control board is installed.
✅ Try inserting the control board into a different PCI slot.
✅ Reinstall the data cables and check for broken pins.
✅ If the board is faulty, replace it.
9. "Three-Axis Alarm, Initialization Error No. 4" Error Message
Problem:
The software displays a "three-axis alarm" during startup.
Possible Causes & Solutions:
✅ Ensure that the data cables between the computer and the machine are connected properly.
✅ Check if the fuse in the adapter board is burned out and replace it.
✅ Verify if the power supply (5V/12V) is functioning properly.
10. Misalignment or Incorrect Size During Engraving
Problem:
The final engraving does not match the intended dimensions.
Possible Causes & Solutions:
✅ Verify that the engraving path in the software is correct.
✅ Check for loose screws on the lead screw or polished rod.
✅ Ensure the software parameter settings are correct.
✅ Check if the ground wire is connected properly.
✅ Scan the computer for viruses that may interfere with operation.
11. Z-Axis Not Lifting the Tool Correctly
Problem:
The Z-axis does not lift the tool at the right time or moves incorrectly.
Possible Causes & Solutions:
✅ Check if the Z-axis motor is operating normally and if the power supply is stable.
✅ Inspect the motor wiring for loose connections or intermittent disconnection.
12. Spindle Motor Does Not Rotate or Reverses
Problem:
The spindle motor fails to rotate or spins in the wrong direction.
Possible Causes & Solutions:
✅ Check the parameter settings of the inverter.
✅ If the inverter signal wires are reversed, swap any two of the three wires connecting the inverter to the motor.
✅ Ensure the wiring between the inverter and control box is secure.
✅ If all wiring is intact and the motor still does not work, replace the motor.
13. Axis Locks Up When the Software is Launched
Problem:
When starting the CNC software, the machine’s axis remains locked.
Possible Causes & Solutions:
✅ Check for a drive issue or poor connection in the output signal line.
✅ Inspect the motor wire for loose connections.
✅ Ensure that software parameters are correctly set.
14. CNC Router Limits Are Reached Unexpectedly
Problem:
The router unexpectedly reaches its limit during engraving.
Possible Causes & Solutions:
✅ Confirm that the engraving path does not exceed the machine's working area.
✅ Check if the software limit settings in the CNC software are too restrictive.
15. CNC Software Fails to Start or Causes Deformation in Engraving
Problem:
The CNC software does not open properly, or the engraving is distorted.
Possible Causes & Solutions:
✅ Reinstall the operating system and CNC software if needed.
✅ Check if the X and Y-axis lead screws or fastening screws are loose.
✅ Ensure the engraving bit is in good condition.
Final Tips for Preventing CNC Router Issues
🔹 Regular Maintenance – Clean dust and debris, check lubrication, and inspect electrical connections.
🔹 Software Updates – Ensure your CNC software is up to date for the best performance.
🔹 Proper Calibration – Set up your machine correctly before each job to avoid misalignment.
🔹 Use High-Quality Tools – Dull or low-quality bits can lead to excessive wear and tool breakage.
By following these troubleshooting steps, you can minimize downtime and ensure your CNC router operates efficiently.
