X axis jams at rapid speed

Machine was running fine yesterday went to do a laser job at 8am this morning it is now 2pm and I still have not been able to press start for the job.
Using gsender to run lightburn code, framed the job and noticed the x axis stuttering and jamming which makes the machine thinks it is somwhere other than it is.
What I have done so far. Checked wheels. Checked backlash nut. motor shaft coupling all good. everything turns easily by hand. I removed the x axis rail and took the gantry off, visually all look OK. Put everthing back together, same issue. I can jog at normal speed without problem, in rapid mode it just jams. Leadscrew and anti backlashnut rails and wheels show no damage. I have spent hours adjusting the wheels and backlash nothing works.
Thoughts anyone

Well looked at it again this am. Took it all apart and confirmed mechanically all was ok. After putting it all back together and confirming issue still present, I put x motor onto the z drive, took off like a champ. I increased x drive power on the board and all works good, I am wondering if I have a drive failing, dont recall ever seeing a drive loose power like this but I have no other explanation.

How much time on the machine? Could it be the stepper getting tired? I had a stepper on my last machine with erratic behavior on my lead screw driven Z that i swap with one of my belt driving Y steppers. Cleared up the issue long enough to get a new motor ordered. I think the nature and duration of the load are different enough sometimes that the change buys time.

Jim, I got the machine on January 19 this year so about 6 weeks. I hear what you are saying but I do not think it is the motor. Since I upped the output from the drive I have noticed that the motor is much quieter and is definately running better. I just ran 2 laser engravings both over an hour long and the motor is barely warm. I am still of the opinion that the drive is the issue. As I say I have never seen a drve slowly loose power but there is always something new to learn. Could kick myself for not thinking of the motor earlier but I was convinced it was a mechanical issue. I intend to let it run as is which could be a long or short time. We will no doubt find out. By the way how you getting along with your current issue.

Yeah, definitely too new to have a stepper going bad!

I’m still waiting to hear from Sienci. My issue is replicable pretty predictably at 40 to 45 minutes of any activity. Essentially, as soon as the steppers are ennergized, the clock is ticking. I think it’s a short in th power supply but it could also be in the longboard. That part is beyond me. It would be easier to diagnose if it was only one axis but it’s all of them at the same time.

With all motors having the same issue it sure seems like power on the board. I have not looked at the board in detail but I would not be surprised if there wasnt a step down from 24vdc to a control circuit of 5vdc that could be causing the issue. I have heard Sienci tech support is very good so I am sure you will hear back. Still a bummer though right out the box. Good luck.

Yeah, I understand a lot of electronics theory but no practical application. I’m guessing once it gets warmed up something air gaps a little and it stops giving me enough juice, either voltage or possibly amperage. The power supply itself was reading 22.4 ish as I recall and fluctuating. I don’t know what kind of tolerances I should be expecting but 10% seems like a lot. I didn’t check it cold so I might be staring at a red herring.

I’d sure like to sort it out though! I have stuff to make!

I had this happen and, embarassingly, the adjustment screw had worked loose from the anti backlash nut behind the z carriage and was jamming in between the carriage and lead screw, causing it to stop moving in the X direction

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