Filament Runout Jig for Roller Guide

thingiverse

I got a filament runout sensor and wanted to find the ideal placement for it while still utilizing the fabulous filament guide from which this is remixed. I tried mounting the guide up near the spool (see mounting plate I made to remix a nice solution for this option here: https://www.thingiverse.com/thing:5691091). I found that I didn't like wasting about a foot of printable filament when it detects a runout when the print head is still near the bed. (Yes, I could stick filament in the sensor and go manual until most of it is printed, but I don't want to). So here's my next try: Create a mobile bracket that moves along just above the filament guide. Now when it detects runout I'm only wasting the length of the bowden tube plus about 3-4 inches, a good amount to grab hold of to remove it from the extruder and bowden assembly. It travels up and down with the extruder anchored on the z-screw and another thinner gear bearing that fits in the v-groove of the filament guide bearing. The thinner bearing also allows the bearing to ride along it's axle in different locations to home in on the right location for the runout sensor relative to the filament guide. I'm watching to see if this leaves any deposit on the z-screw (or binds up movement while printing) or if it adversely affects the filament guide workings. So far I've liked how it responds to retraction (it is "wiggly" enough to absorb backward movement without forcing filament back through the sensor), and how this option doesn't force filament travel through a severe angle from spool to the guide like the top mounted bracket did, especially when the spool was near empty (though the thin-ness of that bracket allowed it to bend and lessen the angle, but still there was pressure on the filament). Time will tell if this bracket is practical (or if it's just janky)! (2/2/2023) Added a revision of the main arm with an extended tail. I was printing something tall and biting my nails at the end because I thought this bracket was going to climb off of the z-screw. I estimated I needed another 4cm or so to span the distance between the end of the screw and the spool without interfering with the spool. Hopefully the added friction doesn't affect anything, I'm printing along and watching!