Z calibration 9th calibration point fail
Hi, I just finished (ok not just i finished yesterday) building my pursa i3 mk2 kit. I am having a strange issue with the Z calibration.
Firmware 3.0.9
Self test: OK
XYZ Calibration: OK (No issues here apart from a slightly skewed XY axis)
Z Calibration: Okish, Nozzle touches the bed at the 9th (back right) calibration point sometimes but not always
Z calibration test print. The probe detects the first 8 calibration points but at the 9th it just keeps pushing down bending the heatbed downwards with the nozzle. Its like the position of the point was not correctly saved or the point is not detected by the probe.
What am i doing wrong here? I couldnt find an answer in the forum so if you have any idea please help me 🙂
Re: Z calibration 9th calibration point fail
I had the same problem. I loosed the nuts holding the Z axis frame to the X/Y axis frame and re-seated the vertical frame, on mine I felt the right side move down which lifts the Z position. After correcting that and re doing the probe/sensor for bed height I have been printing fine.
Try checking that.
Mark
Re: Z calibration 9th calibration point fail
Thank you. Unfortunately this did not help. Maybe i did something wrong but ill try to ajust the whole thing tomorrow again. If you have any other idea id be very happy to hear it.
Re: Z calibration 9th calibration point fail
Just found this reddit post from 5months ago. Calibrating the xyz seemed to help there. Didnt do it for me though. Apparently this kind of behaviour was fixed in 3.0.7? Is it possible that 3.0.9 reintroduced it?
https://www.reddit.com/r/3Dprinting/comments/4v8um6/z_calibration_issue_prusa_i3_mk2/
Re: Z calibration 9th calibration point fail
Alright. I found the reason for the issue. The nylon filament holding the umbillical cord in place at the rambo board had slipped out and caused the pindaprobe connector to slip in and out.
If this is not helping in your case, move the extruder all the way up bevore preheating as heat might confuse the pinda probe. (support told me this)
Re: Z calibration 9th calibration point fail
I have similar issues with calibration point 9 not being found.
It occurs at random, or at least so it seems. I had the printer running since months and the PINDA probe is thread-locked in the right position.
During calibration or during Mesh Bed Levelling the last calibration point does not get found. The extruder moves down, the PINDA light goes out once, but then the extruder lifts up a bit and the LCD announces that the point could not be found and it's waiting for a reset.
The cure for it is to try again and again. Eventually it works without a problem, and then the printer runs well for a while.
I'll have to check the connector on the RAMBo like you suggest.
Re: Z calibration 9th calibration point fail
Alright. I found the reason for the issue. The nylon filament holding the umbillical cord in place at the rambo board had slipped out and caused the pindaprobe connector to slip in and out.
If this is not helping in your case, move the extruder all the way up bevore preheating as heat might confuse the pinda probe. (support told me this)
Is it still working after you fixed this?
I have checked the PINDA connector on my printer and re-seated it, nothing wrong with it, but the random failures to find calibration point 9 continue, during calibration and during mesh bed levelling. I just repeat the "start print from SD card" or the calibration until it eventually works, at random. Very annoying.
Re: Z calibration 9th calibration point fail
Today I again spent at least another extra hour repeating calibrations until I get the "Congratulation" message. 👿
I recorded some videos, they might help to diagnose what goes wrong here. Photobucket was a complete pain to work with today, I'm not sure if these videos will be accessible to other viewers than myself, and if the quality will be sufficient. When I play them back from Photobucket on my computer, the video lags and jumps and is generally poor quality.
The files I uploaded were good enough quality, please let me know if they are at all watch-able. I edited the videos of the failures to be very short. The Success video is longer, no need to watch it unless you don't know what a normal end of Original Prusa i3 MK2 calibration looks like.
The first video shows the failure to find calibration point 9 during mesh bed levelling. Note how the PINDA probe blinks once.
http://i281.photobucket.com/albums/kk217/Mr_Mik/3D%20Printing/th_MOV_0010_Mesh-levelling-failure_cropped.mp4
The second video shows the failure to find calibration point 9 during XYZ-calibration. Note how the Y-axis does not move, but the PINDA probe is blinking:
http://i281.photobucket.com/albums/kk217/Mr_Mik/3D%20Printing/th_MOV_007_xyz_calibration-failure-pt9_cropped.mp4
The third video shows the successful XYZ calibration immediately following the failure shown in video 2 above:
http://i281.photobucket.com/albums/kk217/Mr_Mik/3D%20Printing/th_MOV_0001_xyz-calibration-success_1.mp4
Is there any information contained in the particular blinking pattern of the PINDA probe or the movements of the x and y axis, that could help diagnose the underlying problem?
Re: Z calibration 9th calibration point fail
I ran into the same issue again after I had to reseat the PINDA Probe. Funny thing is, turning the nut by 1/2 and highering (sorry dont know the proper english word) the PINDA probe helped it find the 9th point.
Re: Z calibration 9th calibration point fail
My nephew's MK2 printer was doing the same thing, failing on the 9th Calibration point. It failed with "XYZ calibration failed. Please consult the manual". It would help users if the firmware gave a more useful error message!
I took off the adhesive felt feet, and corrected the Z-axis frame mounting in the frame nuts so that both Z-frame side tabs rest on my work table, and now it has improved enough to get: "XYZ calibration all right. Skew will be corrected automatically"
Chris Shaker