First Layer Calibration Not Performing Bed Mesh
So first off I am new to Prusa with this being my first mini+ (Not new to 3d Printing). Day 1 everything went well but last night (Day 2) my smooth PEI sheet lost a piece with a PETG print (Really bummed out that I only printed 5 items on it before the sheet failed) But anyways I read that the textured sheet was a better sheet for PETG so I installed that went to calibrate the first layer. For some reason it only does the mesh on the first row. (Spots 1-4 of first row only). I perform the mesh option and that works fine so this is localized to just the first layer calibration. The first layer calibration did work for me prior to this so that's why I am confused (currently on Day 3 with printer so could be user error but it feels like software or hardware related)
Diagnostic I have performed:
1) Tried with smooth PEI sheet - Worked fine one time. But then I re-ran the calibration and it only did the first row. So intermittent failure
2) Pre-heat the bed - Figured maybe it was due to the fact I was using PETG and the bed was taking a while to warm - Same result only mesh on first row
3) Tested probe - Probe tests fine. Probe shows readout during all range of motion and if I wiggle the wire harness. Also I can see the probe is reading fine during the first row mesh (Light turns on and off as expected)
4) Change plastic to PLA - Long shot but figured maybe it had to do with the temp the printer was using - Randomly worked once then on next steps went back to first row mesh only
5) restarted printer - I have done this multiple times through the process No effect
6) Factory reset - Another long shot just to rule out me somehow making a setting change but no effect still first row only.
My next step is to potentially re-flash the firmware to see if it has a bug that was resolved but this is a 3 day old machine but it appears I am running 4.3.1 +2759 so maybe that will help.
Has anyone else run into this type of issue? Without proper Mesh leveling I cannot calibrate Z offset. I did notice when I calibrated before that the offset I had to use was -1.9 so very close to the max offset of -2. I was loving this machine up until the smooth PEI sheet tore on me last night (Not something I have had issues with on other PEI sheets on my other printers)
Best Answer by Benford:
Well I was able to identify the root issue. Basically during first layer calibration the machine will not give a notification of a failed probe. It will also not stop the first layer calibration it will simply just stop doing the Mesh level and then proceed with the first layer print. For me it ended up being a loose screw on the front and rear plate. (Mostly assembled kit so not sure if it was missed or if it just happened to work its way out)
Recommendation to Prusa: I would recommend adding an if statement to your code for first layer calibration that will trigger if the mesh fails to notify the user. Also it would be best to also exit the program at that stage as a first layer print without a mesh is basically pointless. Would have saved me a decent bit of work if the system would have alerted me to the issue.
Hopefully this helps someone else in the future
Update
I went ahead and flashed 4.3.3 and calibration worked 1 time then went back to only doing mesh on the first row.
With a new printer I'd get on a chat with Prusa Support, in case this turns out to be a warranty issue. Go to https://shop.prusa3d.com/, log into your account, and then click on the Chat button in the lower right corner.
Update 2.0
Fuchsr,
That is a good idea. I wasn't exactly sure where to start that process. I will open up a chat with them tomorrow most likely. I think I might have found a potential cause for my issue. I found that once I start a print it I got a sensor error. I did some looking around on the machine and found that the far end of the gantry was off the bed more then closer to the tower. I also found that it had considerable wiggle. This was a mostly assembled kit so I review the three screws I put in place (they felt very snug. So I went around other screws and found a few that were a bit loose. I tightened them all up and it has worked fine for the last 2 bed calibrations and 2 prints now. I will give it a few more prints and see if that was the real issue or not. I do still see some flex in the arm itself (I can see its moving by watching the Z rod wiggle in its hole) I am guessing some wiggle is expected with this style printer (when you apply force that is) So we will see if it proves to return or if that was me whole issue.
I will post here if it comes up again or if I do reach out to support.
Thanks for your reply and the link that will help if I end up needing to go that route.
Found the Issue
Well I was able to identify the root issue. Basically during first layer calibration the machine will not give a notification of a failed probe. It will also not stop the first layer calibration it will simply just stop doing the Mesh level and then proceed with the first layer print. For me it ended up being a loose screw on the front and rear plate. (Mostly assembled kit so not sure if it was missed or if it just happened to work its way out)
Recommendation to Prusa: I would recommend adding an if statement to your code for first layer calibration that will trigger if the mesh fails to notify the user. Also it would be best to also exit the program at that stage as a first layer print without a mesh is basically pointless. Would have saved me a decent bit of work if the system would have alerted me to the issue.
Hopefully this helps someone else in the future