X and Z axis motor jitter when spindle turns on

I’m not sure if this has been an issue for others, and I haven’t seen any posts about it. I most recently ran into an issue with my X and Z axis motors jittering (moving in small jolts) when the spindle spools up and is about to carve. Its like it starts drifting by itself. So I tried to plug the USB into another computer and the jitters still occur. When I disconnect the USB and power up the spindle manually the jitters do not occur. What could cause this? I don’t want to risk carving something and the jitters cause inaccurate cuts. Has anyone experienced this before? Could a computer virus cause issues with feedback going through the USB connection? Could the Ardiuno board be having issues with the connection? I have checked all my connections and solder points and all are solid connections. All my belts or set correctly also. Any help would be great. I can get a video I needed.

Which spindle do you have, and how long have you had it?

Have you grounded the shield wires for the stepper motors and limit switches?

Im running the inventables 24vdc spindle…all wires are grounded and ive checked all connections to ensure they weren’t loose. Ive had it for a few months now and probably done 6 or 7 projects or so. Im not running the limit switches anymore since I thought they were causing the problems and removed them.

If you have one of the original spindles, it may be starting to fail. One sure sign that it’s failing is if you have to “finger-start” it. If I understand it correctly, the idea was that the vibration would cause some of the windings to break or come loose and cause enough of an increase in the EM field around the spindle wires (or spindle) that the steppers would occasionally gain or lose steps just from the field. Have you noticed any lost steps, maybe a pyramid type cutting pattern that shows the bit is moving slightly one direction or a return to a different home position? Is there any change in sound, more rattling or chattering than when you first started?

Inventables has got a new batch in that seems to be working great, so if the spindle is going bad then they should be able to get you a new one in prime condition. I went through 2 old ones, each only lasted 10-15 hours, but my new one has more than 20 hours and is still doing great.

At first I thought it was the spindle, but it doesn’t seem to be the issue. My reasoning is that when I don’t have the USB connected to the computer I can turn the power on to the spindle from the power box and the x and z axis stepper motors don’t jitter. The jitter only happens when the USB is connected to the computer.


do you have and solution, yet? I have the same problem right know: Stepper motors moving in small jolts when the spindel is on. But only when the USB is connected.
I did some voltage measurements. There is wired (jumping) voltage on the 24V connector at the X axis. But on the power supply outlet the 24V are stable.

I will rewire the whole machine today and hope that there was some wiring problem.

So I got in contact with Inventables and we did some trouble shooting. They informed me that they were having some issues with the the spindles that caused some electrical feedback throughout the system that cause the jittering in the stepper motors. The spindle ended up burning up on me and melted the wires half way through the wiring. So we then narrowed it down to the arduino board along with the power supply. They sent me a replacement for them all and everything has been working smoothly since. At first we thought it was just the spindle and the power unit on the power supply since the switch for the spindle was only working manually and not through easal. Once I got the new parts we figured it was the power supply and that fixed everything since then. Hope this helps

Inventables sent me a new spindle. Now everything works fine.

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