Z-Axis Troubleshooting

Machines (Original/PRO) Troubleshooting (X35/X50)
1

Evening Everyone:

Requesting assistance on troubleshooting the Z-Axis before i do anything more involved.

Issue: Z-Axis Erratic movements, issue showed up in the middle of a cut with Z-Axis over plunging and breaking a 1/8 bit. Test with controller have shown the same erratic movement.

Machine: Journeyman Pro
HuanYang 220 Spindle/VFD
Extended cables with grounds connected to ground

Steps Performed So Far: (1) Removed all electrical except for controller from circuit, unplugged VFD, Wifi, etc… (2) continuity check on Z cable showed no issues (2) swapped X and Z cable and issue remained.

Thoughts: I would think that removing all electrical I reduced EMI potential to a point it should not be present, combined with me swapping X/Z cables and that should solidify EMI is not the culprit.

While continuity check can be inconclusive, it at least shows no break in the sheath. Combined with swapping cables makes me think the cable is not the issue.

So that comes down to the controller or the stepper. Visual check shows nothing appareent with either. Any idea on how to multi-meter the controller and stepper to see if i can find an issue

OR

Have i missed something more basic. Visual check of connectors showed no bent pins, but could be stepper motor cabling to first connector.

2

Update for all. I disconnected everything cleaned the controller and re-attached all cables. Z -axis misstepping still.

However, I moved the cable, wiggled it, at the controller and got a z axis motor fault.

So it would seem either 1) contrary to the continuity check the cable or connector is bad 2) the controller connector/pins are bad.

3

I am having the same issue. Have tried a variety of things. No solution. The machine be running and out of the blue, Z moves up or down without changing the Z value, obviously under or over cutting. Running a 1/2" endmill so no breakage here. What’s going on???

4

what is your level of skill.

I started by knocking out the basics based on other FAQ/Posts here.

  1. If it is Z-Axis erratic behavior IT IS a connection issue
  2. isolate where the issue is
    a) I did a continuity check on the cable and in reality it forces a connection and probably isn’t accurate but it’s what i knew.
    b) i realized when i moved the z axis cable while using the remote that it errored out, that showed a connection.
  3. visually inspect the connectors in the event its pretty obvious, maybe dirty and causing cennction issues

My fix, i got cable and connectors from amazon ~$60 and i was able to get consistent movement. It was backwards Up=down, but it works. So, it seems to prove that Z-axis erratic behavior is indeed a connection issue.

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5

Hey SgtSilverBack,

This is unlikely. They don’t fail by erratic movements, but usually by failure. The tin-plated Amphenol/Molex contacts used on these machines do not comply to industry standards. They aren’t even suited to be used on the outside of a machine. Typically you know them from ATX power connector on PC mainboards, and don’t ask how many disks failed because of the poor contact. They are made to be connected exactly once and to be used only internally.

Good standard for stepper connectors are Phoenix gold-plated circular connectors. See here:

6

Thanks for the insight, in reality I misspoke when I said controller or stepper, when I meant the connector for the controller or stepper. My assumption was it was connector related and I was trying to isolate which one.

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