Z-axis failure
Have to get advice on a failed print. It appears that the z-axis motors just stopped moving during the print. Before cancelling the print, I observed the z-axis motors slipping with no movement on the axis. This is the third print on this printer, but the first time this has occurred. After stopping the print the z-axis seemed to move smoothly up and down using the controls. I then lowered the z-axis to the build plate and the controller reported z-axis at +3.8, this seem consistent with z-axis slip
Any ideas.
Maybe related, during x/y/z calibration the machine will not do the upward Z move on 4 out of 5 attempts. It does seem to work if I move the Z-axis near the top before starting the calibration. The z-motor threaded shafts seem to move freely by hand when deenergized.
RE: Z-axis failure
If you XYZ calibration fails I would start there by disassembly and retracing those steps. It worked for me.
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Chuck H
3D Printer Review Blog
RE: Z-axis failure
I am currently on a quest to locate the gremlin. I tried printing, re-slicing and printing the same piece and it failed at exactly the same Z-height. I then made a test tower which did not jam up, but did print a very wide layer at the same Z position. I checked the gcode at those heights and it seems to be fine, but there is a ~1 mil high, very wide layer at the same z-height the previous two prints failed, but the printer got past it. It looks like it had a problem getting past that position and printed a few layers worth of filament without advancing along the z-axis, but it would have to have done that over multiple z-height increments to get the effect. Unfortunately I stopped the print early, or else I could have verified the theory by comparing the printed height with the designed height.
You can see in the image, the wide band on the tower at exact same height. I inspected the lead screws for damage and didn't find any. I put pieces of tape on the dust caps, which are currently about 5 mls above their respective motors. The dust caps loose synchronization
concurrently with the fail. I have not been able to see it happen yet, so I can't yet say which shaft is hanging up, but that is where I am looking.
RE: Z-axis failure
The lead screw dust cover nuts (aka jam nuts) can wedge and jam the motors. The T-nuts can also jam, but less likely.
The most common problem is something is snagging a wire or interfering with the X-carriage as it raises up. A wire tie hitting the power supply or Einsy case, a spool holder that is installed wrong, or even a screw tip that goes through the vertical frame to hold an accessory.
RE: Z-axis failure
'aka' jam nuts, got that straight.
All your points of contact are definitely a possibility, but I been over every possible point of contact many times now (2 days worth of effort), so I'm sure it's not a point of contact other than maybe the duct covers. Once the JAM NUTS were moved up, I loosened the z-axis tops and cycled the z-axis at least a dozen times and tightened up the top caps. So for it seems to be printing and calibrating correctly. 3 tall prints accomplished so far with no errors.
Good luck to me.
Thanks for your inputs
RE: Z-axis failure
If the issue continues, post up photos of the frame, rear of the extruder, the cable tail, and spool holder you're using. All angles. Whatever it is/was is mechanical; maybe not obvious to you, maybe obvious to others.
RE: Z-axis failure
@tim-m30
Will do... Thanks