Filament runout sensor

thingiverse

I created this to get the filament sensor working on my R17. It's a simple setup and I didn't use any bowden couplings to secure the hose. Instead, I cutted the bowden hose about 70-80mm below the extruder and pushed both ends into the plastic part. So far, it's worked fine and I don't see any reason for using couplings. One thing that could be improved is when the filament runs out during unloading; it can catch on the edge inside the plastic part and force the bowden tube apart a bit. For me, this isn't a problem, but maybe I'll fix it later. The electrical connection: I purchased some PHR-2 connectors and pins from my local electronics shop along with a micro switch that seemed small enough. Unfortunately, I don't have the article number handy. Connect the two cables to the normally closed connections on the micro switch. If you do this incorrectly, the only consequence is that when you start printing, it will immediately alert you that there's no filament. I have some pictures of it in operation if you're interested. In any case, it works for me! Good luck with your build!