3D Print Your Own Mechanical Filament Meter

If you have an FFF (fused-filament fabrication) 3D printer, you probably rely on your slicer software to tell you how much filament a job will use. But that is just an estimate and probably won’t be accurate. Even your printer’s built-in filament tracking may not be exact, which is why you should take a look at this very nifty 3D-printable mechanical Filament Meter designed by ArduinoNmore.

This Filament Meter works very much like an old school automotive odometer, in that it is a simple gear-driven mechanism. As the extruder motor spins, it turns the meter’s input gear. That then spins three indicator gears: meters, tens of meters, and hundreds of meters. Each gear has a 10:1 reduction from its predecessor, so ten revolutions of the meters gear will spin the tens gear once. But unlike a car’s odometer, this mechanism works in reverse. That means that it will subtract from the filament length count during retractions, which improves accuracy.

Building this Filament Meter is as simple as printing the handful of parts in whatever colors you desire. The design is a derivative of 3D Printy’s counter mechanism and the only other hardware it requires in addition to the 3D-printed parts are fasteners (three M3 screws and two M3 nuts). The parts are printable on just about any printer that can maintain decent tolerances and they don’t require supports. ArduinoNmore designed the Filament Meter to work with an Ender 3, but it should also work with any printer that has a NEMA 17 extruder motor and an 11mm diameter extruder wheel. Depending on the location of the extruder motor, adding the Filament Meter may reduce your build volume as it could limit movement in one or more axes.