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False positive reading from filament sensor
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When I started printing with flexy materials I started getting filament runouts. I had previously been printing with nGen and PLA with no problem. With the terminal open I got this error

[12:11:53] Remaining mm: 1.52, 12.09
< [12:11:54] Remaining mm: 0.75, 12.09
< [12:11:55] Remaining mm: 0.36, 12.09
< [12:11:56] Remaining mm: 0.11, 12.09
< [12:11:57] Remaining mm: 0.01, 12.09
< [12:11:57] Pausing print
< [12:11:57] //action:filament_runout
< [12:11:59] Remaining mm: 13.81, 14.00
< [12:11:59] Remaining mm: 13.36, 14.00
< [12:12:01] Remaining mm: 13.12, 14.00
< [12:12:01] Remaining mm: 12.77, 14.00
< [12:12:03] Remaining mm: 12.40, 14.00
< [12:12:03] Remaining mm: 12.00, 14.00
< [12:12:05] Remaining mm: 12.00, 14.00
< [12:12:05] Remaining mm: 12.00, 14.00
< [12:12:07] Remaining mm: 12.00, 14.00
< [12:12:09] Remaining mm: 12.00, 14.00
< [12:12:09] Remaining mm: 12.00, 14.00
< [12:12:11] Remaining mm: 12.00, 14.00
< [12:12:11] Remaining mm: 12.00, 14.00
< [12:12:13] Remaining mm: 12.00, 14.00
< [12:12:13] Remaining mm: 12.00, 14.00

It looks like it ran out then started reading the filament again.

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Event Timeline

MikeR created this task.Jan 3 2019, 2:30 PM
MikeR triaged this task as Normal priority.

@MikeR are you seeing this issue still?

MikeR added a comment.Jan 11 2019, 8:39 AM

@DaniAO I have not seen this issue since I switched back to using nGen. I was having too much trouble with the flexy that I had to change. I don't know if there is anyone else who has tried printing with flexy material other than josh to see if they have the same problem. It looked like the flexy filament was getting jammed somehow and would stop extruding after a few layers.

I had difficulties printing flexy as well. Gave up on it.

MikeR added a comment.Jan 11 2019, 8:57 AM

HEre is the gcode I was using. Nozzle one was ninjaflex and nozzle 2 was polyflex.

@MikeR what was the runout detection setting used in this print? Can you try turning the runout detection higher and test again? I wonder if we shouldn't make this setting defined in profiles as flexible materials may require a higher threshold.

MikeR added a comment.Jan 11 2019, 9:55 AM

@Steven I first had the runout set to 14mm then I increased it to 34mm. Both ended up running out.

oliver added a subscriber: oliver.Jan 11 2019, 10:07 AM

Trying to run flexy with just one extruder right now and I had this happen on the first layer for me. Attempting a second try and I can get the run out threshold when it fails or if it happens to complete.

The job I was currently printing finished the entire print for the most part. Slice settings needs some adjustment but it did finish. This was also only using extruder 1 to print and I believe @MikeR was seeing this when his started printing with extruder 2.

I am running a flexy/PVA print with the filament sensor turned on (set to 14mm). PVA on extruder 1, Flexy on extruder 2. I have had no issues with the sensors and false positives. @west is printing another dual flexy cone, and i dont believe he has seen any false positives with flexy either.

@MikeR have you tried to run flexy again lately?

MikeR added a comment.Jan 16 2019, 1:22 PM

@tutley I have not printed with any flexy recently. I may have had an issue with my tensions with the flexy. Once I get my printer put back together I will try it again.

matth added a subscriber: matth.Thu, Feb 21, 10:01 AM

Firmware .91, Cura 3.6.4

Been trying to do a large print, but twice now it stopped after an hour or so with a false positive. Jeff believes it's because of the fact I'm using 2 3kg reels and since there's not too much wiggle room with them, it's easy for filament or the reels themselves to get caught on something and prevent filament intake. I make a ticket about that here: T5813

matth added a comment.Wed, Mar 6, 9:10 AM

Currently on .93

I don't know if it's the sensor or the tool head, but I've been getting a lot of false positives lately. Sometimes I can reproduce them, sometimes I can't, and it'll occur mid print. Twice now I've had a long (12+ hour) print stop about an hour into printing and I have no idea why.

MikeR added a comment.Wed, Mar 6, 10:40 AM

@matth is there any chance you could jabber me a vid of it? I may be able to help.

jebba added a subscriber: jebba.Wed, Mar 6, 2:03 PM

Btw, I was just speculating it could be the weight of the reel, since it started happening when we put a new black 3kg Polymaker PLA reel on the machine. Could be 100x other things.