Bed level correction 50 µm is not enough  

Re: Bed level correction 50 µm is not enough

...I noticed that I have scratches on the rods by bearings. Can this affect?...
might be, if the scratch is deep enough and the balls of the ball-bearing run inside the scratch.

...Is it a good idea to change the maximum value of bed level correction in firmware?...
😕 hmmm... hard to tell. don't know if the limitation was put in place due to calculation restrictions (to avoid the overflow of some variables).
at least the variable is handled as an unsigned char, so it shouldn't exceed 255.

➡ i think you'll only find out if you recompile the firmware with another value for the BED_ADJUSTMENT_UM_MAX (you'll find it inside the ultralcd.cpp, line 1371 or so).
i would try out a value of 100 or max. 127 .... no risk, no fun

---- update ----

just googled for the bed_adjustment_um_max and found this link where eriobis contributed a change of the manual correction level to 150 at github.

Re: Bed level correction 50 µm is not enough

...I noticed that I have scratches on the rods by bearings. Can this affect?...
might be, if the scratch is deep enough and the balls of the ball-bearing run inside the scratch.

...Is it a good idea to change the maximum value of bed level correction in firmware?...
😕 hmmm... hard to tell. don't know if the limitation was put in place due to calculation restrictions (to avoid the overflow of some variables).
at least the variable is handled an unsigned char, so it shouldn't exceed 255.

➡ i think you'll only find out if you recompile the firmware with another value for the BED_ADJUSTMENT_UM_MAX (you'll find it inside the ultralcd.cpp, line 1371 or so).
i would try out a value of 100 or max. 127 .... no risk, no fun

Re: Bed level correction 50 µm is not enough

First try was quite a fail 😀

https://github.com/prusa3d/Prusa-Firmware/pull/77/files
This guide is way better than original on github so I was able to do it right. In my case the variable was on line 1509. In addition, I see 2 new options the Temp calibration and PID calibration.
I will do some test prints tomorrow.

Re: Bed level correction 50 µm is not enough

❓ you haven't seen this thread by allen.d ?

➡ without his script it's quite a pita to get the firmware compiled successful. with his script it's easy as pie.

Re: Bed level correction 50 µm is not enough

❓ you haven't seen this thread by allen.d ?

➡ without his script it's quite a pita to get the firmware compiled successful. with his script it's easy as pie.

Re: Bed level correction 50 µm is not enough

You can get up to 101 microns adjustment using G80 with L/R/F/B plus the value as in this example:

G80 F101 B70 L-10 R101

Peter

Re: Bed level correction 50 µm is not enough

Hello @ all,

yes, I have the same problem. For me are 50µm to less. If I calibrate the printer bed middle perfectly to z axis, then is the distance in front between bed and extruder to high and in the backside to low.

Is it possible to expand the range without modifying the .gcode?

Best Regards
Tim

Re: Bed level correction 50 µm is not enough

As I said before, I updated the firmware to this: https://github.com/prusa3d/Prusa-Firmware/tree/MK2/Firmware
I did calibration XYZ and everything was good enough that I didn't change anything.
Apparently the new firmware is better in calibration.

@tim.e2 Update the firmware and check.

Re: Bed level correction 50 µm is not enough

ah.... fw 3.0.10-10 now (last one i've downloaded was the previous -9, last one compiled the 3.0.10 released version).
think it's time to update my printer(s) now... with some tiny tweaks about the level correction, verbosity level and the submenu timeout.