Filament motion sensor

thingiverse

This is a detector I designed to verify if my 1.75mm filament is actually moving. This becomes especially useful when troubleshooting filament feed issues. You can examine the extruder drive wheel, but it can spin without feeding filament. It utilizes half of a rubber band that you receive on broccoli at the supermarket. It attaches with the bowden connector to my MK8 extruder from Geeetech. I am including the 123Design file so you can modify to fit your situation. Each segment of the wheel represents about 7mm (7.15 to be exact) of movement. There is a video of it in operation that can be seen here https://youtu.be/JHtcuPsRDpk Enjoy! Print Settings Printer: Geeetech Pro Rafts: No Supports: No Resolution: 0.2 will do Infill: I used 80% to get some strength around the mount Notes: Uses M3 nuts, bolt, washers, (2) 3X7X3 bearings and a rubber band. Post-Printing You will need to drill out the filament guide holes using a 2mm drill bit. Cut a broccoli rubber band in half lengthwise and stretch around the wheel. I used a sharpie to highlight the markers on the wheel to promote visibility.