Z-Calibration Issues
Hi,
I've been trying to get the printer going for a while now, and I'm completely out of ideas. I have a Prusa MK2 kit that I assembled, and I managed to get it to do an XYZ calibration to 'slightly skewed', and I did a live adjust Z that came out to about -1.75mm, and I managed to get a few good prints off of it. Now, it won't seem to hold its live adjust.
I've tried lowering and raising the probe and it doesn't seem to help with the issue. So I think it's a compound of two issues:
1) Right now, my probe is about ~.8mm away from the tip, which seems to be what people on the fourm recommend. (It also matches up with the diagram in the video, with aligning the top of the probe with the frame) This means I need a live adjust of almost -2.5mm, which seems somewhat extreme to what other people need.
2) The live adjust isn't constant, and varies a lot. If I can get the V2 calibration to print a nice, properly pressed line, the next print starts out either with the tip a mm in the air or pressing into the board.
I've looked through the fourm, and I've seem similar issues, but does anyone have an actual fix? Or even a patch? Could it be something to do with the probe? I've seen people mentioning that it's maybe a superensitivity to temperature, but I've tried to keep the y-axis up during heating but it doesn't seem to help. Maybe the inverse and keep it really low during both the initial z calibration and heating, so it always is heated to bed temp?
I'd love any advice on this, starting to pull my hair out.
Re: Z-Calibration Issues
First thoughts: Your probe is very sensitive. It will also be sensitive to heat. So when you pre-heat the bed, ensure the extruder is at least 100mm above the bed.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Z-Calibration Issues
Hi Peter,
Thanks for your response. I've tried keeping the probe up when it preheats, but it'll heat up during the print. Should I modify my post-run code to raise it up, and just always wait for it to cool down completely? I confess I do try and do the calibrations back to back.
Re: Z-Calibration Issues
So, the probe doesn't seem to be quite working right. The light on it is starting to occasionally remain out, even when out in the air, and it behaves as if it's triggering up there (the entire z-calibration takes place while at the top of the axis). After restarting it, instead of doing the usual three up/down it did it faster on one of them and then failed on the third. If I want to get a new probe, how do I order it?
Re: Z-Calibration Issues
PINDA probes are listed ion a hidden spare parts section of the Prusa Shop. In order to get access to this hidden section, make sure you're logged in with your account, then use the Chat feature (lower right corner of the screen) and ask Support to give you access to the spare parts section.
Apparently PINDAs are currently out of stock, so maybe ask Support not only for access but also for an "emergency" PINDA replacement and see what they can offer you.
Re: Z-Calibration Issues
Hi are you still having an issue with your Z and did you try the replacement PINDA yet?
Re: Z-Calibration Issues
Hi,
Thanks for the response. I actually had to walk away from it for a week to avoid raging at it after I realized it had scratched the board too when it was attempting to calibrate one time. I'm going to be ordering the replacement PINDA today (or at least trying)
Thanks
Re: Z-Calibration Issues
If its not square now is the time to do that. Get on a step stool and look directly down to make sure the x axis lines up perfectly square with the line on the bed. If not tweak adjust the spacing of the bolt nuts that connect to the overhead frame, and get it square.
Re: Z-Calibration Issues
Lochlin,
I'm dealing with the same issue but the symptoms are a tad different. Here's the URL to my question so you might want to take a look at it as more people comment incase they mention something that you may want to try http://shop.prusa3d.com/forum/prusa-i3-kit-building-calibrating-first-print-main-f6/pinda-probe-issues-cannot-keep-z-offset-t3930.html . Does sound like a broken probe though as the issue isn't consistent.
Totally feel you about the rage-quit deal though. I've been doing that for months. I just wanna print!!! I'm wondering if someone should start a stickied topic with a bunch of stories like this, the symptoms, and how the issue was rectified so other people have an inventory of problems/solutions to peruse.
Benjamin