HD6 Coupler Reset

Images show the HD6 X-axis for reference. This procedure is identical for all HD6 X/Y axes and the X/Y axes of the HD644.

IMPORTANT: Remove coupler set screws with a hand tool only. Power tools may strip the screw heads. Be sure that the bit is fully seated before turning. 

To reset the Z-Axis coupler, see HD Coupler Reset

Coupler/Shaft Collar Access: 

X/Z Axis

Y Axis - The coupler and lead screw are enclosed in the base frame. You can access both by either removing the red aluminum top, or via the access points located in the image below. 

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Resetting the Coupler

1. Prepare the machine

• Move the machine to the end of travel where the motor is mounted.
• Power off the machine and disconnect all cables from the motor.
• Remove the four (4) bolts securing the motor.

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2. Remove the motor and disconnect the coupler

• Carefully pull the motor straight back.
• The coupler will separate:
  • One hub remains on the lead screw
  • One hub remains on the motor shaft
  • The red rubber spider may stay with either side or come loose — this is normal
• Loosen the set screw(s) on the coupler hub attached to the motor shaft.
• Slide the coupler hub off the motor shaft.

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3. Reposition the lead screw

• Rotate the lead screw by hand until it protrudes through the motor opening in the aluminum base end. If the hub on the lead screw is loose, be sure to tighten it.

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4. Reassemble the coupling on the lead screw

• Place the spider between the two coupler hubs.
• Slide the motor-side hub back onto the lead screw hub.
• Make sure all three pieces (hub, spider, hub) are fully seated together.
  • The spider should sit fully in the jaws.

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5. Install the motor into the coupler

• Align the motor shaft with the open coupler hub.
• Gently slide the motor shaft into the coupler.
• Once the shaft is fully seated, tighten the coupler set screw(s) securely.

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6. Secure the motor

• Rotate the lead screw as needed until the motor sits flush.
• Reinstall and tighten the four motor mounting bolts.

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7. Verify shaft collar and thrust bearing (critical)

• Check the shaft collar on the rear of the lead screw.
• It should be pressed firmly against the aluminum base end with the washer between the collar and the base.
• If needed:
  • Loosen the shaft collar set screw(s)
  • Push the collar firmly against the washer/base
  • Re-tighten the set screw(s)

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8. Final checks

• Confirm the lead screw does not move in and out axially.
• Reconnect motor cables.