Notifications
Clear all

[Solved] Selftest in X failure, but hardware looks fine  

  RSS
primefac
(@primefac)
Active Member
Selftest in X failure, but hardware looks fine

I am honestly not sure if this is a software or a hardware issue, but in brief:

The printer fails its selftest, giving the "please check axis length: X" error, but it still prints. However, our prints are offset (in X) by about 1cm. This isn't an issue for smaller prints (and the reason why we didn't notice it until recently) but any print that is sliced near the edge of the print bed ends up going off the side.

I took everything apart and re-assembled it again, and the issue still presented.

I then did some diagnostics using Octoprint: I ran a first-layer calibration in order to get the X/Y coordinates of the beginning of the print (G1 X50 Y155). After the first layer calibration had finished, I re-homed the print head and then sent it the same G1 command, but this time it ended up where it should have landed in the first place (i.e. ~1cm to the left of the actual print start).

I can't think of a reason why it would go to the right place when not printing, then the wrong place when printing, if it is a hardware issue. Is this a firmware bug?

Posted : 05/06/2023 11:52 am
primefac
(@primefac)
Active Member
Topic starter answered:
RE: Selftest in X failure, but hardware looks fine

Printing on the MK3S+ with the MMU2 upgrade, for reference.

Posted : 06/06/2023 7:42 am
Robin
(@robin)
Prominent Member
RE: Selftest in X failure, but hardware looks fine

It seems more like a hardware problem. Did you do what the printer asked you to do: please check axis length: X ?

This is most likely be cause by something blocking your x-axis on the left hand side. Push your extruder all the way to the left. Where does it hit first? It should be all the way to the left without any bit of the smooth rod showing between extruder and the orange part.

If at first you don't succeed, skydiving is not for you.

Posted : 10/06/2023 4:32 pm
primefac
(@primefac)
Active Member
Topic starter answered:
RE: Selftest in X failure, but hardware looks fine

I know this comes across as a snarky answer, but yes, I did check to make sure there are no obstructions. The zip ties all clear, the cables clear, everything goes where it should (and when it does the x-axis self-check, it does go completely from side to side).

Posted : 14/06/2023 8:24 am
Hello
(@hello)
Noble Member
RE: Selftest in X failure, but hardware looks fine

I'd recommend taking off the gear and belt off motor then re running yes you will get the error of course but watch for stutter when nothing is connected to it if you can put a black dot on the motor metal bit then film it and upload here 

Please help me out by downloading a model it's free and easy but really helps me out https://www.printables.com/@Hello_474427/models

Posted : 14/06/2023 8:29 am
primefac
(@primefac)
Active Member
Topic starter answered:
RE: Selftest in X failure, but hardware looks fine

Well, I'm an idiot. One of the bearings was out of position; I fixed it and the issue has resolved itself. So yes, definite hardware error. Thanks all for the thoughts.

Posted : 07/11/2023 1:10 pm
Share: