Would it be possible to use an IR optical switch to trigger pause, lift and shut off heater when the switch is closed (light detected by emitter)? Then hitting play will resume printing after you have loaded new filament.
@Alex_Hayden If it is just a switch, you can use the switch module : http://smoothieware.org/switch to do what you want. It will trigger a pause and a custom set of G-codes when the filament out is detected, and then when you resume, it can also trigger a custom set of G-codes. It’s all on the wiki.
@Arthur_Wolf thanks. Just what I wanted to see.
I have a plain roller switch with a ptfe tube and printed part doing something similar, Alex. As Arthur said its in the switch docs, well described, and you can have an extra endstops as the resume button, but I have had some quirky behavior with that one, and I prefer to use the “resume” button that will show up at supported hosts like Pronterface and Octoprint.
@raykholo thanks for the picture. I will probably try it both ways.