Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:5158978.
This is an improved version of a device that combines a filament rounout sensor and a filament jam sensor. It is made of two Mini Limit Switch, SPDT Snap Roller Lever Arms connected together. The first sensor for the runout is set to HIGH when filament is in, and to LOW when filament is out. The second sensor for the jam is set to LOW when their is no jam, and to HIGH when the filament tangles and pushes on the lever. For the wiring, the common pin (C) of both sensors are connected and related to the JST connector. The normally open (NO) pin of the jam sensor is connected to the normally close (NC) pin of the runout sensor, and to the JST connector. On the gantry support needs to generate supports for the print. All other parts can be printed without supports.