i3 Mega S with BL-Touch temporary nozzle height problem

[stoertie]

Hi all,

I am not very familiar with Github and hope you will forgive me if I ask my question here. I have not found out how to set the "help wanted" label.

Since yesterday I have a BL-Touch sensor on my i3 Mega S. The firmware I have installed is MEGA_S_TMC_BLT_1_5_2, in which "EnableDevice", has switched off the melodies again, as in the version without BLT befor. (Thank you very much!)

The entire set-up process went perfectly, the automatic levelling works fine and the printer also prints (mostly) without any problems.
Yesterday, however, I suddenly had the problem that the nozzle was too low above the print bed and the material could hardly be pushed out. Luckily I was sitting next to it and was able to cancel the print. I then did a new auto levelling, restarted the print and everything went fine.

This morning I ran a longer print... Everything worked perfect. After I started the second printout, the print head went so deep into the print bed that the printer just chattered. (a terrible noise!)
I switched the printer off and on, did a new auto levelling and now it prints again without any problems and the first layer was also perfect.

I use Cura 5.5.0 as a slicer and have connected the printer via USB.

What could be the reason for the print head sometimes being positioned too low? Does anyone have any ideas?

Best regards
Michael

[alexaring]

I can confirm that I have currently similar issues, you are not alone. I suspect that "sometimes" the z endstops are not working. I will going back to 1.4.4 and try to figure out if the problem is gone and report back.

That's all what I can say to this and yes it is a terrible noise... luckily it is at in my case when I am homing. Sometimes it doesn't happen especially when I do auto-leveling before. I saw some other open issues that sound similar.

[stoertie]

Hi Alex,

yes it's really strange.
I have had this issue only before I posted my problem.
Since I posted this issue everything works well. Also after doing the auto-leveling several times everything works perfect.
So, for me and at the moment, there is no reason to go back to the previous firmware.

Regards
Michael