Filament runout sensor Ender 3 Pro

thingiverse

This is a mount for the stock Ender 3 z-endstop to use as a filament runout sensor, It mounts to the frame using the original z leadscrew guide plate screws for a very solid installation. It also prevents the filament from touching the z rod. You can use a small piece of PTFE tube if you are worried about the filament rubbing against the part. The z-endstop mounts using the original two bolts, the holes are a little tight so you might need to tap them with the screws first. I didn't like the positioning of the sensor of https://www.thingiverse.com/thing:3409178 so i remixed it by integrating it with the filament guide block i was using: https://www.thingiverse.com/thing:3127620 If you are using Marlin Filament runout you should set this as filament runout script: FILAMENT_RUNOUT_SCRIPT "M600 U0" this prevents the extruder from automatically retracting the remaning filament that would ram the underside of the lever of the endstop. On runout detection the printer will park the nozzle, then you have to manually unload the remaining filament by pressing down the lever with a small screwdriver or hex wrench and turning the extruder knob. This mount is perfect if you use a side spool holder. I use Spool holder side mount https://www.thingiverse.com/thing:3564351 8mm spool holder adapter https://www.thingiverse.com/thing:4745939 Quick change universal spool holder https://www.thingiverse.com/thing:1241566