As the bearing of the idler began to wear down and get stuck it grinded down the rubber housing of the bearing. Instead of just buying a new one I just opened the bearing, cleaned and relubed it so that the bearing was fine. But i was missing a rubber housing for it. So I designed one from ground up. I made one for PETG “press-fit” since i only had PETG laying around but later made one with proper notches so that a TPU version won't slip of the bearing.
Hope it helps you like it did for me.
Needs no supports, but I had to print it with 101% on one of my printers while the other was fine with 100% so you maybe have to try some scaling.
I even made some version with proper gears but never printed them. Those need supports and I don't know if the gears fitting all chains out there. But the one without gears was working so well I never printed the gears one.
The author marked this model as their own original creation.