Prusa MK3S MMU2S Extruder Idler + Filament Sensor Sensitivity Increase

thingiverse

This is the exact Prusa i3 MK3S MMU2S extruder idler with two layers added to the part at the top that breaks the filament sensor beam. I modified this piece because I was trying to pair PETG and a Flex filament. I found that the Flex filament was too squishy to push the idler out enough to engage the filament sensor reliably. I tried tightening the idler spring, but once it was tight enough to grab the PETG, it was too tight to detect the Flex. The only way to solve my problem was to make the filament sensor less sensitive. I did this by adding two layers to the piece at the top of the idler that breaks the sensor beam. It is now a gentle trigger, and can detect both PETG and Flex at a loose spring tension.