Octoprint Filament Run Out Sensor
Updated: Learned alot since this post, scroll down for updated instructions
(I dont know if any one has posted this already. But it was new to me and solves a big problem with a lot of 3d printers so I’m sharing.)
Octoprint is great. I love watching my printers while I’m working. (Octoprint Anywhere pluggin). I love getting picture progress and completion reports on my phone (pushbullet pluggin). Octoprint is just awesome.
Hate almost empty spools of filament laying about because your afraid they cant finish a print?
Do you use new rolls of filament on a big prints because a half empty roll might run out before job is complete?
Or maybe you check constantly, babysitting the printer if a roll is almost finished.
Im done with that. The sensor linked below works with Octoprint to pause a print if filament runs out. Once filament run out is detected, the print head moves away from model and cools down until you change filament. (Filament Sensor Reloaded)
So then come back to printer. Heat up extruder, change filament, extrude a little, hit resume on Taz 6 and then click resume on Octoprint. Then 
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The sensor has 3 wires. But you only need red and white for it to work with Octoprint:
Red > GPIO 4, which is pin 7
White > any ground pin (I used pin 6)
filament reloaded (1).jpg
Octoprint gcode scripts:
After print job is cancelled -
G91; Set to Relative position
G1 E-6 F300; retract the filament a bit before lifting the nozzle
G0 Z50; move z axis up 50
G1 Y150 F5000; move part out for inspection
After print job is paused -
M600 Z50; pauses print then moves the print head up 50mm so hotend doesn't burn model
So just mount the sensor into the filament path. Connect the wires to Octoprint. Add pluggin to Octoprint. Configure pluggin and reboot Octoprint.
The sensor comes in a 3d printed case. For now I just have it in the filament path, which has worked out so far. Im a noob at designing, but someone can whip up a better implementation. Some1 on thingiverse integrated a different filament sensor into the filament tube, which is awesome.
I think this method is a lot easier than adding the sensor to the printer itself. That would involve modifying the firmware and splicing the sensor into your printers circuit board. Which is a possible warranty issue. Besides Octoprint has so any other benefits this just puts it over the top.
There isn’t anything special about the module, it’s a standard mechanical endstop housed in a 3d printed case. So you could make your own. Just a matter of positioning the endstop so a break triggers it.
Amazon on Sensor
