Small Geared Extruder with filament runout sensor

Small Geared Extruder for a NEMA 17 motor. it uses the knurled filament driver gear.

This design also includes a microswith based filament runout sensor. it uses M5 pushfit fittings for input and output for the 4mm bowden tube.

Drive Gear: https://www.ebay.co.uk/itm/322433693693?var=511408080059

Tension Spring; https://www.ebay.co.uk/itm/10-pcs-Leveling-Extruder-Springs-for-Reprap-Prusa-Mendel-3D-Printer-Pop-TH/253300987468?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

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