PVA/BVOH filaments incompatible with MK4 MMU3.
Lots of filaments are available for MK4 but are incompatible with MK4 MMU3. The most important one is PVA/BVOH which is more or less unusable without MMU3 but when using MMU3 they are unavailable. I believe I can hack the filament settings but this should really be done by Prusa...
PrusaSlicer 2.7.4
RE: PVA/BVOH filaments incompatible with MK4 MMU3.
Prusa only include filament/printer/nozzle combination that they have tested and know works with a high degree of reliability. That has ALWAYS been the case.
If you can not find the combo you want then either they haven't tried it or its not reliable enough to be included. Of course Prusa never tell you which of those is the case. Make up your own mind.
If you want to raise the issue woth Prusa then you need to do it at the appropriate github repository. This is a user to user forum and things raised here do not generally get dev attention.
The PS github is here https://github.com/prusa3d/PrusaSlicer/issues
Looking through the existing issues it seems there are a couple related to wipe tower problems when using BVOH as it can cause collapses. Maybe that is why its not available to MMU profiles.
RE: PVA/BVOH filaments incompatible with MK4 MMU3.
I've opened an issue on GitHub
I remember experimenting with my MMU2; to prevent cross contamination and consequent very weak prints you have to purge enormous amounts at every filament change. Soluble supports and single extruder sytems aren't really economic. It's just about doable for cleanly supporting overhangs on trinkets but for anything structural it's almost always going to produc a a good looking, flimsy, functionaly useless part.
Cheerio,