Z-Axis Motor Screech

Hello again,

I’ve run into a new issue that has brought me to a total standstill. First, some specs:

-Moai 130
-Peopoly Heater
-Advanced FEP Acrylic/Tank
-Advanced Build Plate
-Custom 24V distribution terminal for main board power, heater, and side-mounted thermometer w/ built-in thermostatically monitored relay (power from 24V 10A PSU)

Whenever I try to run my printer, 9 times out of 10 when I turn it on, the Z-axis screeches/whines and won’t move. I’ve replaced both the power supply (10A to a 5A) and the z-axis, as well as reinstalled the firmware (1.18). The screeching is coming from the motor itself; when I try to move the axis by hand I am met with little to no resistance. I’ve already ordered a new internal power board with the thought that maybe something on that was problematic, but I’m beginning to suspect that the main board may have suffered an issue to some extent.

Has anyone else ever experienced this? It use to happen very infrequently (although it did ruin prints when it happened), but it progressively got worse and now I can’t print at all with my Moai. I can upload photos at anyone’s request, just not sure what would be pertinent at the moment. Thanks in advance guys, every problem I’ve run into I’ve managed to solve with your guy’s help!

if you can film the boot up of your Moai so we can see the problem, that would help a lot

Boot Up Z-Axis Sound

I think that link should work for you!

I did some further digging and it appears that it may indeed be the main board. Upon further testing, I was able to solicit a proper response from the z-axis but it involved pressing inward on the connection (towards the center of the board). When I inspected the board, it appeared that the pad for the 4th pin was lifting (not sure how that could have been possible though, board was installed and left alone until now) and not making contact with the trace and the connection was only made when that pressure was made to push it into contact.

that’s actually a normal thing if the build plate is already at the top
if you manually lower the build plate, and reboot, the z axis should go back up and make the sound

Thanks for the info, however that was not the case this time. The z-axis wouldn’t move at all, even if manually moved from its’ endstop.

I was waiting for my replacement main board to arrive before replying and today it came and was installed. After installing the new main board, I am happy to report that everything has returned back to normal. That screeching that was being heard was not part of normal start up and was a symptom of a solder pad lifting on one of the lines going from the z-axis motor connection to the Z-axis stepper driver. It was allowing for incomplete/inconsistent power to the stepper which was causing the screeching and, eventually, failure of the z-axis motor to move.

@peopolysupport if you want more info on this, I’d be happy to get some photos of the old board and show you what was happening. While I did some light power distribution modifications to the Moai, I never touched the main board once it was installed during the initial build so I’m unsure how the lifted pad could have occurred. I would like to recommend that if anyone else has this issue, investigate the pads as part of your diagnosis. I was surprised to see this was the root cause but am happy to have rectified it.

i’m glad that you got it sorted out, but please notify us 1st next time.
You are quite lucky that the problem is exactly the main board, if it was a faulty z motor then it would have been a waste of money