An attempt at a filament sensor...

I kinda like the idea of using an optical encoder on a nondriven roller to detect when filament is no longer moving through. I’ve had far more clogs, jumped filament, tangles, etc than times where I reached the end of the line. Maybe I’m just good at checking the slicer filament requirements before starting and eyeballing my spool :slight_smile:

@Greg_V @Baldur_Norddahl Repetier can read an encoder and check filament travel distance, and will even try slowing down print speed to recover before pausing the print. There’s also the Tunell Filament Monitor for sale (google it) which will monitor filament motion and send a pause command to any board with an open input pin if the filament stops turning a wheel.

Jam-detection is a very-much solved problem… people just don’t want to pay the money for an easy solution or deal with the wiring for a cheap solution. That’s why a simple out-of-filament switch like Preston’s is appealing… easy AND cheap.

@Greg_V I tend to print large objects, so fewer objects per spool, and a greater chance of hitting end of spool in an object.

Had exactly one(?) tangle in the past year. Maybe I am a bit more careful(?) or the manufacturers I favor are better(?) wound.

(Just realized “wound” as in injury, and “wound” as in a form of winding are different pronunciation with the exact same spelling. Who says English is irregular?)

I did buy one spool of cheap PLA from a popular vendor on eBay that … mostly … printed OK. (The light purple wings as single wall prints back in my stream.) Was suspect, so kept a constant eye, and manually intervened often. Never tangled, but left alone, might have. (Not planning on re-ordering from that vendor.)

About jams, I have no opinion. With experience, proper hotends, and decent filaments - does that problem go away? No notion, as yet.

Also the ordered limit switches should arrive today. Impatient, as obtaining obscure technical components manufactured somewhere else on the planet takes two whole days to arrive. #FirstWorldProblems

I admit i generally don’t print anything very large. What i hear both @Preston_Bannister and @Ryan_Carlyle saying is that you’d rather save a couple bucks on a switch and recurringly spend it on more expensive consumable filament and high end hot ends? Not saying there is one right answer here, just that my conclusions were differently driven.

FWIW, I have Tunell monitors on two of my workhorse printers and another one waiting for an overhaul to install a monitor. I don’t bother putting them on my various experimental printers that don’t get a ton of use, because the filament of the occasional failed print is cheaper than the time/money cost to buy parts, design mounts, configure firmware, etc.

If you want to be cheap, one could implement the encoder wheel with 3d printed parts only. It would be a wheel that alternate between shorting and open two wires. Just like the brush in a DC motor. Does not look to be hard to design or implement at all.

@Greg_V Paying about $20 for a 1Kg spool, or a bit less - print mostly 3D Solutech, MakerGeeks, Inland - so not pricey stuff.

For me, filament-out is my most common problem, so my first interest. And this approach is simple to add to all my printers.

Trying out different hotends as I want to print larger prints in less time. With a larger 0.8mm nozzle, found a mk10 hotend seemed to hit a thermal limit at ~9mm^3/s. The newly-installed V6 hotend seems to hit the limit at ~12mm^3/s. These are very rough measures, and seems to vary with filament. Not done methodical tests as yet.

(Or maybe this is an extruder limit, as much as thermal?)

Have not yet tried the Volcano kit. Wanted to try the Ubis 13HF at some point, but not sure that is still possible. :frowning:

@Preston_Bannister from your various posts, it’s apparent to me you’re doing all kinds of amazing things, and i really appreciate your sharing them here! If you are going through filament fast you probably aren’t running into issues with filament age as a variable either, but for a lot of people, that can be a concern that might be a further reason for clogging.

FWIW, this one seems to work. The diameter of side hole/guide for drilling a notch in the tube is the tricky bit.

@Greg_V Thanks, but if I showed that much ego, there are folk here who will offer prompt correction. :slight_smile:

That is pretty much the point of the exercise. I will make mistakes, but if they are “smart” mistakes, that provokes discussion, and folk with more experience in this area tend to have a variety of views. The examples and discussion should help pull forward everyone.