unable to complete calibration wizard after reattaching thermistor  

Re: unable to complete calibration wizard after reattaching thermistor

Hi Ken

I've watched your video through and I think I can offer at least some assistance.

The wizard runs the XYZ calibration. This raises the Z axis right to the top to level both sides, then makes sure you do not have a steel sheet on the bed, then it asks you to use a piece of paper to tell if the nozzle crashes. Up to this point all is normal. The next part is where it goes wrong. The Z axis descends but then it stops around 100mm or so above the bed. This should not happen. Z should descend until the PINDA detects the first point and then the XYZ calibration routine continues. Yours is failing immediately because the Z axis cannot descend to the bed fully. Unless this issue is corrected you cannot proceed and it is why manual attempts to bed level are failing - because the XYZ is not completed.

Hard to say exactly why this is happening not being in front of the machine but there have been a few cases of the black trapeziodal nuts on the Z axis leadscrews being too tight. I suspect this may be related, or your Z axis is not correctly assembled causing the X carriage to bind. If the nuts are too tight you will need to talk to support to obtain replacements.

So when you are running XYZ calibration the Z axis should be able to move freely and fully right to the top of the lead screws and all the way back down until the PINDA detects the first left bottom corner point on the bed. You need to examine why that is not happening - once that step can complete you should be able to calibrate the printer successfully.

I hope that helps a little,

Re: unable to complete calibration wizard after reattaching thermistor

Hi Ken

I've watched your video through and I think I can offer at least some assistance.

The wizard runs the XYZ calibration. This raises the Z axis right to the top to level both sides, then makes sure you do not have a steel sheet on the bed, then it asks you to use a piece of paper to tell if the nozzle crashes. Up to this point all is normal. The next part is where it goes wrong. The Z axis descends but then it stops around 100mm or so above the bed. This should not happen. Z should descend until the PINDA detects the first point and then the XYZ calibration routine continues. Yours is failing immediately because the Z axis cannot descend to the bed fully. Unless this issue is corrected you cannot proceed and it is why manual attempts to bed level are failing - because the XYZ is not completed.

Hard to say exactly why this is happening not being in front of the machine but there have been a few cases of the black trapeziodal nuts on the Z axis leadscrews being too tight. I suspect this may be related, or your Z axis is not correctly assembled causing the X carriage to bind. If the nuts are too tight you will need to talk to support to obtain replacements.

So when you are running XYZ calibration the Z axis should be able to move freely and fully right to the top of the lead screws and all the way back down until the PINDA detects the first left bottom corner point on the bed. You need to examine why that is not happening - once that step can complete you should be able to calibrate the printer successfully.

I hope that helps a little,

Alfred,

Thanks for watching my video - it had to have been painful... There are a couple of reasons why I don't think it's something mechanical with the Z axis. The first reason is that I had been printing just fine until the thermister came loose from the heat bed. In repairing the thermister all I did was remove the heat bed, turn it over and then re-attach it. I did manually raise the x-axis a bit so I had more room to work but I didn't do anything violent to it. The second reason is that I can unplug the printer, manually set the hot end just above the bed, plug the printer back in (the info screen says z = 0) then go to the Settings menu, Move Axes, Z axis and move the z axis from 0 to 210 and back to zero again with no problem. I was going to film this fact and discovered that my camera battery needed to be charged...

Anyway, to make a long story great, while waiting for the battery to charge, I unplugged and re-plugged the printer several time with the z at different heights (which each time it assumed the value to be 0) and then ran the z up to the top (banging into the mounts as expected). That "seemed" to define the z as 210 and I could then move it all the way to a 0 right above the build plate. I took a chance and restarted the wizard. It got all the way to the final step - setting the first layer height (i.e., through all the bed leveling gyrations) and then stopped well above the bed complaining about possible deposits on the print head... I unplugged it again, manually set the nozzle just above the metal sheet, plugged it back in, went to Calibration, First Layer Height and set the value that produced a good squish. I've been printing ever since.

I don't understand what the problem is and it could come back to haunt me at any moment. What I do know is that I'm able to print.

Thanks again.
Ken

Re: unable to complete calibration wizard after reattaching thermistor

The important bit is you are up and running however you got there. Happy Printing!

Re: unable to complete calibration wizard after reattaching thermistor

The important bit is you are up and running however you got there. Happy Printing!

Hi Alfred,
It has bitten me again. I'm working with support to get to the bottom.
Ken

Re: unable to complete calibration wizard after reattaching thermistor

For what it's worth. My PINDA probe had failed. Support sent me a new one (grey) with a much thicker cable. Calibration completes just fine now and I'm printing again without concerns.

Re: unable to complete calibration wizard after reattaching thermistor

Thanks for posting the resolution Ken, it all adds to the repository of knowledge. Glad you got sorted!