Calibration Test Failure
The initial self test on my printer went well enough. The next step failed in a distinctive way right at the start though—the extruder just lowered itself straight down to the hot plate, and didn’t do anything else before returning an error telling me to check the Z axis.
Can anyone tell me what I need to fix?
RE: Calibration Test Failure
https://help.prusa3d.com/article/fja7hbb22y-xyz-calibration-error-messages-mk-3
RE: Calibration Test Failure
The exact error (tested it again today) is "Calibration failed! Check the axes and run again." This happens every time, soon after the 12 minute calibration test prompt, and right after the sensor lowers directly into the plate. It also isn't one of the errors listed in that link.
RE: Calibration Test Failure
The exact error (tested it again today) is "Calibration failed! Check the axes and run again." This happens every time, soon after the 12 minute calibration test prompt, and right after the sensor lowers directly into the plate. It also isn't one of the errors listed in that link.
Is your pinda probe activating? The light should be on when the nozzle is raised up and goes out when it reaches the calibration point on the heated bed. If the light doesn't go out when it should, but does go out when you hold a piece of metal to the bottom of the sensor then you need to adjust the distance from the end of the pinda probe to the heated bed, needs to be about the thickness of one of the zip ties.
RE: Calibration Test Failure
The light goes out as the extruder reaches the heatbed, the moment it touches I think. Which makes me think I just need to lower it a little bit more. It seems as if I just so happened to almost but not quite get it right from what you said.
And... well, lowering it by just 1 screw thread stopped the extruder from slightly damaging the heatbed at the corner by lowering straight into it. It still produced the same error message though. I think I did do the zip tie trick... mostly correctly, but it was slightly off.
Also, on my printer, I wasn't able to lower the Pinda sensor (except by twisting/untwisting it) without pushing the holding part outwards using a green stuff sculpting tool to give me enough space. Seeing as the issue seems to be centered on that sensor, I figured this detail may just be relevant.
RE: Calibration Test Failure
I just ran into the same problem. All I did was I changed the muzzle. As such, I'm pretty sure my axes are OK.
1. Selftest - OK
2. XYZ Calibration, go up the Z to hit the top
3. Extruder goes down, seems to stop at the right distance and displays error
There is one thing which I noticed and bit bothers me. When I do the Auto Home from the Calibration menu, the sensor ends up above the center of the first point (+- a milimeter or two). But when the the XYZ calibration starts, it displays "Auto home", but the sensor ends up about 1cm off the center of the calibration point.
In regards to the sensor, it's active up until the extruder gets down to the heatbed, then goes off and the error is displayed. And btw. as someone mentioned earlier, the error "Calibration failed! Check the axes and run again." isn't mentioned anywhere in the guide.
RE: Calibration Test Failure
Try going even lower with the PINDA. As long as it is marginally higher than the nozzle tip, it won't be hitting the model. The zip tie trick didn't work on my printer, the zip tie was too thick for the purpose and the PINDA too high as a result. I needed to go about 0.5mm lower.
RE: Calibration Test Failure
It's not a matter of sensor height. The extruder stops consistently with the sensor what it seems to be at the right height (as far as I can remember was the height before I changed the nozzle).
I just did a test with the sensor lower than the nozzle, extruder still stops with the sensor at the "right" height so it's obvious the PINDA is working.
Again, the displayed error is undocumented. I checked the 2.6 version of the MK2.5S and there is no mention of this.
Btw. I tried the Mesh Bed leveling and it works like a charm getting through all 9 points with no problem.
RE: Calibration Test Failure
You do seem to be experiencing the same error as me, Juraj. Everything you've said matches with what I've experienced myself.
As frustrating as it is, it's nice to know I'm not the only one experiencing this issue.
RE: Calibration Test Failure
This error seems to printed by the firmware when the Z calibration fails because the Z is unable to move freely all the way to the top or when it isn't able to move the expected Z distance between Z top end and PINDA activating. This is typically some problem with assembly, like the acetal threaded Z nuts being installed upside down, the motor cover nuts being too tight, the X assembly being askew, cables getting in the way somewhere, or extruder assembled wrong.
Photos of the printer and video of the failure could help diagnose more. And checking everything against the assembly manual, of course.
RE: Calibration Test Failure
What you suggest is reasonable Vojtech, but if you read carefully, I had a fully functional printer and I did print quite a bit of models with it. All I did was change the nozzle and start the Calibration Wizard (which reset the parameters so I can't just return back and just try to adjust the Z axis).
So when you suggest the problem is with the assembly, I'm pretty sure it's not my case.
RE: Calibration Test Failure
My printer was newly assembled, but I have a feeling it may be what Juraj's current issue is. I may take a second look over it later, but right now, I'm keeping an eye out for something that'll answer both our problems.
RE: Calibration Test Failure
In my case... the head was lowering enough to cause a bit of a bend in the bars for the y axis. Adjusted things so it wouldn't lower that far, but still no luck on a successful test.