Did PrusaSlicer 2.9 Alter the MK4+MMU3 Mesh Bed Leveling Process? - Hardware, firmware and software help

RE: Did PrusaSlicer 2.9 Alter the MK4+MMU3 Mesh Bed Leveling Process?

dr_stefan_krank — Mon, 06 Jan 2025 15:02:18 +0000

The firmware can handle non MMU3 g-code, but after looking into the source code of the printers firmware, it makes some assumptions to get it working.
Because it loads the filament before bed leveling, I had a lot of oozing and I had to babysit the start of the print to remove the dripped down filament before it really starts.

Conclusion: If you have the MMU3 connected, always slice with the MMU3 printer profile, even when only using one filament. It also prevents the manual intervention at the printer when sending to directly print as well.

Side note: A MMU3 sliced g-code with only one filament used also works on a non MMU3 printer with a little hint at the start about missing features. I use this to bypass the MMU3 when printing TPU without changing the printer profile in Prusa Slicer.

RE: Did PrusaSlicer 2.9 Alter the MK4+MMU3 Mesh Bed Leveling Process?

Spug_Yeti — Sat, 21 Dec 2024 21:16:25 +0000

I believe I figured it out. I think I sliced the gcode as MK4 and not MK4 MMU3. I'll test shortly and will respond to this thread if it's not resolved (if no responses are made, assume my resolution is correct). Nice to know the MK4 MMU algos can handle MK4 gcode.

Did PrusaSlicer 2.9 Alter the MK4+MMU3 Mesh Bed Leveling Process?

Spug_Yeti — Sat, 21 Dec 2024 18:25:02 +0000

I updated to PrusaSlicer 2.9 today and noticed a change in how the MMU3 performs Mesh Bed Leveling. Prior to the update, my printer performed the leveling step BEFORE loading filament, but after moving to v2.9 those steps are swapped. The previous process was advantageous as it nearly eliminated the filament dots left behind when the Nextruder touches the print sheet during leveling.

Does an option exist I can toggle to restore the previous process (or is there a good reason I shouldn't)? Thanks!