Help! Odd Behavior, can't calibrate suddenly

[truenorthtrader]

Hello!

I was printing fine, then suddenly on next print, the Nozzle wasn't moving flatly across the Onyx bed, 1st layer won't print evenly, towards Z it pushes into the glass removing some of the glue stick glue
Note I have the first of the Rostocks but upgraded the Onyx over a year ago.

This is a small 3 inch diameter circle, it should print it even if not calibrated perfectly. I calibrated it 4 times and every time it pushes into the Z axis.
Looking closely at it, as it's making the circle, it's up towards Y axis, going down towards Z and up and down around X axis.

I've had this a long time and printed many many items, I don't get this.
I calibrated multiple times, checked cheapskates, checked motor pully's for tightness, reinstalled firmware after doing Eeprom clear but it still doesn't travel flat across the bed.


Anyone experience this before?
many thanks in advance

[BenTheRighteous]

Do you have the metal u-joints? Did one of them seize up against the rod?

[truenorthtrader]

Thanks so much Ben, took each joint and rod off cleaned rods and arms reassembled, same problem.
I was so sure it would do the trick as they were almost all dirty but to no avail. Even after 2 calibrations for center and XYZ axis it still does the exact same thing.

puzzled. :/

[Eaglezsoar]

Ensure that the drive pulleys are still tight on the motor shafts. This sounds as though something is either stuck or is slipping.
The best of luck finding the little gremlin!

[truenorthtrader]

Thank you, yes checked that first tightened them hasn't helped, looks like I'll have to take the belts off and thoroughly check everything.

[teoman]

Have any conditions changed recently?

Moved printer or such?

I had similar problems, and some of them were related to the end stop switches picking up noise.

If you search the forum, there is a recommendation to switch off checking the end stops after homing is complete. It is rather easy to do.

If it shifts early enough, then one of the carriages does not move up so when it moves back down it digs in to the build surface.



Edit:
http://forum.seemecnc.com/viewtopic.php ... eck#p64019

[PartDaddy]

End stop wires parallel to stepper wires will pick up noise and cause skewed prints; but it doesn't seem like that's it because you've been printing already.

If you haven't solved it yet, I recommend hopping on our Chat. Or email our [email protected] .

[truenorthtrader]

Thanks you teoman for the link! Really helped, I think it's the motors as the problem is exactly the same and everything else is good on my printer. Luckily I have 4 extra's so will likely change the Z tower motor.
I've had it since the Kickstarter so I imagine 1 or more motors are going since I've used it alot.
I already replaced the Y axis motor as the shaft broke early on.

Thank you if the motor change doesn't work I'll email the support!

I'll update the result when I get a chance to change the motor for others who may encounter this problem.
thank you all again, you guys are awesome!