SFS 2.0: filament path, a design flaw - filament hits walls near output holes

[arekm]

That's one big problem with SFS2.0 filament sensor. Pain to use.

Current design of output holes in filament path is like this:

Just a small diameter hole. That filament needs to hit in perfectly.

In my experience, especially when having longer PTFE tubes installed on both ends of SFS2.0 sensor it is almost impossible to push filament out via that hole. That's because even tiny curvature of filament (by that I mean just filament taken from spool - it won't be straight, it will take a shape of spool) or side tension on filament causes it to hit a wall on left/right side of that exit hole.

I have to unplug PTFE tube on "entry" side and manoeuvre filament blindly inside SFS2.0 sensor, so it finally hits the exit hole of the sensor. It's pure pain to do that each time.

Perhaps a funnel shape would be better, directing the filament from the edges and directing it towards the center of the exit hole.

(note - this is just to show of what shape I mean; so don't look at actual type of operation shown there in fusion cad software)

Consider such improvement on 2.1 iteration. That would have side effect of sensor not being bidirectional anymore but...

(In theory we could just improve and print own, better case for it but CAD model is broken (https://github.com/bigtreetech/smart-filament-detection-module/issues/45))

[osvch]

I'm facing this issue heavily- I'm happy that it was already posted. @bigtreetech what would be mitigation plan for the users?

[roykrikke]

+1

[2Balu2]

+1

[osvch]

@2Balu2 @roykrikke I tighten the PTFE connectors, and before filament insertion- I straighten it as much, as I can- that helps a let with filament transition.

[noobydp]

Try rotating the sensor 180 degrees, and shove the filament in the other direction.