How to use a full spool of filament with the filament sensor?
Hey there,
after some poblems due to the assembly my Prusa MK3S worked fine so far, but after I´ve finished some spools of filament in the last few weeks, I´ve recognized a weird problem.
My Prusa MK3S is not able, to finsih a complete spool of filament.
When the last piece of filament is running into the printhead the filament sensor got triggered and the printer want´s me to unload the filament. But it´s always stuck and can´t be unloaded. I thought it might be caused by the end of the filament, which is sometimes a little bit bent, so I removed the end. But that didn´t helped for me.
Any ideas?
If I´am around the printer, I unload the filament before the last piece is going into the printhead and waste these 5-10cm. Thats cheaper than disassembly the whole printhead. :/
RE: How to use a full spool of filament with the filament sensor?
This is almost the exact topic I came here to start. If I notice I'm running out, I stop it before it gets there. If it runs out on it's own, it keeps going until the filament is nice and level with the top of the ptfe, and then stops. The only way I've found back from there, is to replace the ptfe.
What is the filament sensor actually for? What's the expected behaviour here?
RE: How to use a full spool of filament with the filament sensor?
Recent firmware releases include a feature to allow you to open the extruder and fish out stuck filament when doing a filament change. I haven't had the filament pushed down so far that I can't pull it out with needle-nose pliers on a run-out event. It's usually filament breaks that require more of a tear-down.
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RE: How to use a full spool of filament with the filament sensor?
Depending what I'm doing I often just chase the last remnant of the previous roll with the start of the next roll. Takes a bit of practice but I prefer it if I don't want to interrupt a print for a change sequence and get a zit on the surface. But otherwise those short scraps also serve as great purge pieces when trying to get rid of a dark color like black - chase through 1 or two and then load the real filament 🙂
But I have a skelestruder with exposed gearing I use as a thumbwheel to do this, probably a lot trickier if you have the stock setup.