Re-printing spindle  

There have been different designs on prusa printers and thingiverse. 

more perimeters would normally be better than more infill...  but if you are only doing a short length of the model, changing perimeters would cause a weak point between the areas with different numbers of perimeters... 

lots of infill can cause problems with printing, so I tend to use more top and bottom layers where I want solid plastic... 

Please see the attached .3mf file... 

Modifier Meshes can invoke parameter changes in select areas, again see the attached .3mf file. 

regards Joan

mesh

THANKS!

I'm a pretty unsophisticated Prusa SLicer user, and I needed that word 'mesh' to find the right way to modify the part.  I thought it would be in a menu, not by right clicking the part.

yes... 
some things are not so straight forward!
Have you seen this knowledge base article? 
https://help.prusa3d.com/en/category/prusaslicer_204
regards Joan

RE: Re-printing spindle

I had a similar experience with my MMU2S unit. After pulling my hair out (what I have left that is) for about 2 months, I had followed all the forum articles for some ideas what the problem was and how to fix it. I was about to dismantle the unit and give it up as a bad job. However I decided to give it one last go and stripped it down (what was there to lose). It was only when I did that i found that the idler had a crack at the two bolt clamping area, but this was not noticeable until I had dismantled it, the crack actually ran down the inside of the shaft opening. I then printed a replacement part from the printable parts supplied by Prusa. I used PrusaSlicer with settings 0.15 layer and 20% infill. The print actually turned out looking better than the supplied part?? I also printed a new MMU2-front PTFE holder as I noticed that it was a bit rough looking, I think this was due to  the many jams and failures I had encountered in the past. When I rebuilt it and reinstalled it I wasn't confident that it would be any better, but was pleasantly surprised that  the unit actually worked. There were a few hiccups on loading at the start but now it seems to have settled down and is printing now without any intervention. I have been running prints now at 14+ hours and so far it's going well. I never thought that it would be this good. While I had it dismantled I fettled some parts around the pully body, replaced the PTFE tubes with slightly bigger bore ones and made sure that everything was aligned correctly, as per the official build instructions.  I hope this helps others, it certainly worked for me and I now have a working MMU2S unit, yes so it does work, just takes patience.