RE: bed not level - mesh bed leveling does not compenstate
I fixed this with some steel springs instead of the 6mm spacers under the heatbed. The fine tuning takes a while, but the results are good.
RE: bed not level - mesh bed leveling does not compenstate
When BML doesn’t seem to be doing the right compensation, two things can help:
- Pre-heat the bed and let it sit at target temp for 5 minutes before performing BML
- Pre-heat the PINDA/MINDA probe to 35C before BML
- Combine 1. & 2.
Granted, these are my experience from my MK3S, I don’t have a Mini, so can’t guarantee it’s applicable.
The reason 1) can help is that the heat bed will expand during heatup and there’s no guarantee it won’t keep doing it after hitting target temp. The firmware assumes the bed does not change shape which can lead to wrong compensation. Similarly for 2) the heated bed will heat up the PINDA probe during BML which means that first and last point can be probed at vastly different PINDA temps and firmware does not calibrate for the lower spectrum (<35).
Some people don’t seem affected by these things though, YMMV.
RE: bed not level - mesh bed leveling does not compenstate
When BML doesn’t seem to be doing the right compensation, two things can help:
- Pre-heat the bed and let it sit at target temp for 5 minutes before performing BML
- Pre-heat the PINDA/MINDA probe to 35C before BML
- Combine 1. & 2.
Granted, these are my experience from my MK3S, I don’t have a Mini, so can’t guarantee it’s applicable.
The reason 1) can help is that the heat bed will expand during heatup and there’s no guarantee it won’t keep doing it after hitting target temp. The firmware assumes the bed does not change shape which can lead to wrong compensation. Similarly for 2) the heated bed will heat up the PINDA probe during BML which means that first and last point can be probed at vastly different PINDA temps and firmware does not calibrate for the lower spectrum (<35).
Some people don’t seem affected by these things though, YMMV.
If you did have a Mini, you might realise steps 2 is not possible, the MINDA does not have a temperature sensor. This has been the subject of a lot of discussion in the Mini forums.
Good point about the bed temp though. I have a delay in my start gcode which helps a little.
RE: bed not level - mesh bed leveling does not compenstate
It’s nearly the end of 2020, we have FW 4.2.1 and still MBL is not compensating for the poorly machined bed. I cannot use the entire bed, not even get the 1. layer calibration to stick on the right hand side of the bed. ☹️
Cheers,
Martin