PLA will not re-load after unloading
link to my reddit post about this incase I missed something: https://www.reddit.com/r/prusa3d/comments/dktiks/filament_cannot_reload_at_pla_temperatures_mmu2s/
I can easily use PETG and print from multiple filaments, ABS can load and reload without cutting the tip, and if I start it at 255, PLA can load and reload, however once it unloads at 215 it will no longer reload, even at higher temperatures. I took the hotend apart and did everything I knew how to in order to remove any possible clogs, cold pull, switched the nozzle, dumped cleaning filament through it, no changes. The PTFE tube is slightly damaged at the entrance, however that is not where the issue is, as the filament will go into the PTFE to where my current hunch is that it is an issue with the heatbrake. However I have not been able to remove that to check it more thoroughly as I am afraid of breaking it off inside of the heatsink or stripping the threads.
What baffles me is that it is only PLA and only if the filament was unloaded at less than ~225 C. Measuring the tips with calipers, the difference between the PLA and PETG tips both unloaded at their normal operating temperatures is about 0.05 mm (~2.05 for PETG and ~2.11 for PLA). PLA loads just fine with a freshly cut tip, but because of this issue I cannot print multi material with PLA unless I want to stand there and cut the tip every time it unloads.
I loosened the extruder gears as much as possible with no change.
Bondtech gear grub screw is tight.
F.I.N.D.A. is calibrated.
Everything works fine if not reloading PLA filaments (either single material or PETG multi material).
All firmware has been updated.
Cutting back several inches of the PLA does not make a difference after the first load.