Problems with new Laser Filament Monitor

[ShawnC]

Regarding the filament monitor, can we use Prusa MK3 filament sensor as well? Can it be connected to E0 end stop?

[T3P3Tony]

@shawnc said in Problems with new Laser Filament Monitor [SOLVED]:

Regarding the filament monitor, can we use Prusa MK3 filament sensor as well? Can it be connected to E0 end stop?

No it cannot be used because it does not have the control circuitry on it.

[dc42]

@shawnc said in Problems with new Laser Filament Monitor [SOLVED]:

Regarding the filament monitor, can we use Prusa MK3 filament sensor as well? Can it be connected to E0 end stop?

No. The Prusa filament monitor uses a raw I2C interface to communicate between the sensor and the processor (and it's level shifted to 5V). We rejected that approach because I2C is a bad choice for connecting devices over more than a few cm, because of its poor noise immunity, the lack of any error detection, and the difficulty of recovering from I2C protocol errors. It may be possible to get it working reliably enough in a closely controlled system like a genuine Prusa i3, but it would be a support nightmare if used more widely, e.g. in home-build printers.

[3dmntbighker]

Solutech clear green PETG

Duet3D laser filament monitor on endstop input 3, disabled, allowed movement 40% to 120%, check every 3.0mm, current position -1.7, brightness 107, shutter 17, measured minimum 31%, average 79%, maximum 97% over 17533.6mm

[3dmntbighker]

Matterhackers Ryno clear:

Duet3D laser filament monitor on endstop input 3, disabled, allowed movement 40% to 120%, check every 3.0mm, current position -5.7, brightness 99, shutter 17, measured minimum -4%, average 69%, maximum 93% over 7284.9mm

So far my filament success rate hardly warrants using this sensor. Many dip into negative numbers.

[hayseed_byte]

This post is deleted!

[insertnamehere]

@hayseed_byte said in Problems with new Laser Filament Monitor [SOLVED]:

hayseed_byte 5 Nov 2017, 23:09

I really thought if I spent $180 on a board that it'd pretty much work out of the box and come with some clear instructions. I'm pretty handy with tools (I'm an industrial maintenance tech) but I've been working on this thing for two solid days and I'm still not printing. One of my Z steppers wouldn't do anything but stutter so I poked around with my multimeter for about an hour but didn't really change/repair anything and now both Z steppers are working fine but the Y stepper is going in the wrong direction. It was working fine before. Seems like random problems. Damn thing doesn't want to stay connected over wifi, either.

The cheap GT2560 I had wouldn't let me update the firmware and I got tired of having to change the stepspermm for the z-axis (upgraded to leadscrews from threaded rod). I ordered a $40 RAMPS that was basically DOA so I thought I'd go ahead and spend the money and get what everyone said was the best controller on the market because I was starting to get tired of working on my printer more than I was printing. Dropped $180USD and I've been working on it all weekend. A lot of that was spent re-crimping those damn PITA connectors, though.

I don't mean to rant. I'm just really disappointed. The cheap board had some annoying problems but at least I could print. A lot of time and money spent to make my printer worse off that it was before.

https://www.wildbot3d.com

Right back at you maintenance boi.

[3dmntbighker]

3D Solutech black PLA

Duet3D laser filament monitor on input 3, disabled, allow 40% to 120%, check every 3.0mm, current pos 4.0, brightness 95, shutter 17, measured min 15% avg 47% max 77% over 3105.0mm

I thought I had improved things by installing a clip on top of the Bondtech to keep the sensor from moving around as much with retraction. There goes that theory.

[3dmntbighker]

3D Solutech silver PLA

Duet3D laser filament monitor on input 3, disabled, allow 40% to 120%, check every 3.0mm, current pos -0.5, brightness 104, shutter 17, measured min -2% avg 91% max 196% over 986.7mm

That's about the worst I have seen.

[dc42]

Yes, that's bad! I'm surprised, I would have expected silver PLA to be easy for the sensor to track.

[brunofporto]

@dc42 Having a lot of trouble (needed to turn it off!!!) with purple PLA from Cliever (Brazilian manufacturer)

The average below 50% but the total length very close to the theoretical from slicer - so that is curious.

[dc42]

@brunofporto said in Problems with new Laser Filament Monitor [SOLVED]:

@dc42 Having a lot of trouble (needed to turn it off!!!) with purple PLA from Cliever (Brazilian manufacturer)

The average below 50% but the total length very close to the theoretical from slicer - so that is curious.

The total length is the length commanded (not measured).

[insertnamehere]

I've removed the [SOLVED] for this thread as clearly some users are still having issues.

[3dmntbighker]

Filamentum Rupunzel Silver

Duet3D laser filament monitor on input 3, disabled, allow 15% to 125%, check every 3.0mm, current pos -0.4, brightness 79, shutter 15, measured min 40% avg 93% max 181% over 12606.4mm

I have a had quite a few prints with no issues lately, but here we go. This may be no surprise with the glitter, but this is amazing filament. I started a Google Sheet to track the numbers in case I want to start actively managing each filament to adapt the laser to the filament.

[3dmntbighker]

Sainsmart black PETG:

Duet3D laser filament monitor on input 3, disabled, allow 15% to 125%, check every 3.0mm, current pos 9.2, brightness 100, shutter 17, measured min 14% avg 62% max 93% over 317.2mm

[brunofporto]

I am having issues using the sensor... It does do a lot of false errors as it detects and pause the print even when there is no issue and with a very broad tolerance (0% to 200%!!!!)

For example... it ALWAYS pauses with my start g code, does not matter the filament:

G32
G29
G1 X17 Y0 F10000
M116 
M98 P/macros/SubMacros/beep.g
G4 P30000
G1 Z0.2 ; 
G92 E0 
G1 Y5 E10 F1000 ; Purge 1
G1 X77 E9 F1000 ; Purge 2
G1 X107 E12.5 F1000; Purge 3
G92 E0 

[wilriker]

@brunofporto You try to push 10mm of filament into the hotend which only moves 5mm on the line saying "Purge 1". These are about 24mm³ of plastic spread on a 0.2mm layer height makes for an extrusion width of 24mm - I have a feeling that your hotend is not able to comply to this command.

The second purge tries to create an extrusion width of 1.8mm which is again quite something to ask for.

The third one wants to go with a 5mm extrusion width.

I don't see a way how your extruder would be able to press this much plastic out though I might have an error in my math.

[brunofporto]

@wilriker I was pretty sure it is my fault

Your answer solves this part lol

But still: how to avoid so much false detections during print?

[dc42]

@brunofporto, I have a firmware update on the way that may help, provided the problem isn't that the sensor can't see that particular filament clearly enough.

Have you made sure that there is a only very short piece of PTFE tubing between the filament monitor and the extruder inlet, secured at both ends, so that when the extruder reverses the filament is forced to run back through the sensor, and not bunch up between the sensor and the extruder?

[3dmntbighker]

For the record in my case lashing down the sensor made a big difference. Of course many filaments simply don't work with this sensor. But keeping the sensor from moving around was very important. I don't know how it even works with a bowden