All of sudden my V4 has been acting very strange during its G34 leveling sequence. In the video, you can see that it goes through its normal 3 point leveling and then randomly it decides it doesn’t want to travel all the way to next point and it just does it’s leveling it some other spot. But once it returns to the previous point it is all out of position and then crashes.
It hasn’t always done this and at first it was random (not every print). But now it is pretty much 100% of the time I believe.
Wow that’s an odd one for sure. My first thought was grub screws loose on the motor pullies but after watching the video it sounds like it purposely stopped there. You can hear the motors stop turning. I also didn’t see anything get hung up or hear any skipped steps. Probably still a good idea to check the grub screws just incase. Which firmware are you running?
Ok its been a LONG time since I had marlin on either of my V1 printers. But unless you changed something in the firmware nothing should have changed as far as G34. I wonder if something with Octoprint is messing it up? I don’t think it should be able to but I also don’t use Octoprint either.
I definitely have not touched the Marlin firmware/source code. But bypassing Octoprint is an interesting thought. Not sure that would do anything but I will try running a G34 directly without Octoprint and see what happens.
Next thing I guess is make 100% sure that your wires going to the tool head aren’t catching anywhere. It makes no sense why it would be working just fine and then all of a sudden do crazy stuff like that with zero firmware changes. Its going to be something stupid. That’s what it always ends up being for me anyways lol.
watch the belts as it moves around and make sure they aren’t walking up on the pully. I have seen that before and it will make it do weird things.
I thought about wiring being an issue, but I don’t see that being the case with the stepper motors. With it being a CoreXY motion system it would take both X and Y steppers faulting at the same exact time for it to stop in one spot. I have had it before where I have an issue with one motor stopping and it would cause it to move in one direction only. In this case, they both come to a stop.
You mention wires to the tool head, what on the tool head could be causing the X and Y to stop? Maybe the probe itself is disconnecting and reconnecting?
I was more thinking about them hanging up somewhere on the printer and pulling back on the toolhead. I don’t think that’s the case. But worth looking at anyways.
Well it has been two months and this is still plaguing me. I have to watch the G34 operation every single time to make sure I cut the printer off if/when this happens. I’d say it happens about 60%-70% of the time. It will happen in other spots during the G34, its not always exactly in the same spot as the above video.
I have checked that there are no wires being tugged on while the machine is moving. Even if so, what wire could come loose that it would stop the G34 in the middle of a travel move? Makes no sense.
So today I went ahead and changed to a completely fresh SKR Pro to rule that out. New controller, new flashing of the firmware directly from the Github, same issue….
