I've been going back and forth with support regarding the MMU2s and the default profile is now looking much better. I've been printing both single and multi colour and it is:
- Much more reliable (less loading errors)
- Good Tip formation on the filament between changes
- Good balance between speed and reliability (well for multi material)
While the new profile is much better, and is usable... .these are the areas for improvement (maybe in the next version):
- Unnecessary initial unload/load: The profile load a filament, does the prime strip, moves to the wipe tower then does an unnecessary unloaded/load. Not only does this take time but also leads to a poor first layer for the first block of the wipe tower (see pic where you can see only half of the 1st block of the wipe tower has been laid down).
- There is also an unnecessary movement during the filament change, where the nozzle is hovering over the wipe tower, the next filament is loaded then the head moves over the print then back to wipe tower to do the purge. There is no need to go over the print at this point.
- S3D print two layers of each colour (makes sense) but the 2nd layer of the purge tower does not need to be 100% Infill, again wasting time and material.
- Smarter Wipe Tower: At present the wipe tower is specified by size and is 100% infill.... It should be defined by the amount of filament to be extruded to purge between colour changes. This current setting leads to to a waste in time and filament.
- Wipe to Infill / Wipe to 2nd object: Other options to help with wast and speed would be wipe to infill and a 2nd object that you can specify as the purge tower where you don't care about the colour change
- The current method of assigning a colour part to a process is not that intuitive. It would be better to have one process where you assign a colour part to an extruder. The current method makes sense if you have different filaments, but I'm guessing most MMU prints are the same type of filament but just different colours.
I've also been playing with the size of the purge tower. Attached is a 5 Colour pic with a small purge tower of only 10mm. This works OK for changes between bold colours but is not good for a change from Bold to Light. I'm currently trying a 13mm purge tower on a 3 colour print.
The new profile (which you can get from Support) is much better but I fear the above suggestions will need a change to how S3D works and may be in the next version. Like all S3D profiles you will need to mod to suit your setup (for temp etc).