filament flow error

[corsocesar]

Hello everyone.
for some time, on my cube pro, I have an f12 error which prevents me from printing. I changed everything, nozzle, extruder, motor, PTFE tube but still this error f12.
I do not know what to do.

[TommyDee]

This is likely a sensor failure on the motor controller board. The system monitors the black and white 'flags' on the filament drive wheels. If that is not getting processed or something is wrong with this sensor circuit, the system will read it back as an error - basically, the system things the stepper motor is not feeding filament.

[corsocesar]

In fact, in the extruder metal cooling tube, there is a ptfe-like tube with an outlet diameter smaller than the inlet diameter. I changed it for a standard ptfe tube, same input and output diameter, I installed version 2.02 and change the chip at the back of the extruder, with the filament sensor.
for the moment, everything is working.
I do not know which manipulation to work

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I will still control the system step by step as you said, and see if there is a problem with his.
In any case, thank you for your quick response. I spent sleepless nights looking for the problem and without this forum, I will not have found.
I am also looking for the cables to pass it in three extruders but I can not find them anywhere, if you have an opinion, I am interested.

[TommyDee]

Some people here have parted out machines and offered parts. Sometimes they show up on Ebay. It is hard to find parts. Feel free to post for parts in CubePro for-sale/trade section. Here is a good template from the Cube3 - http://www.print3dforum.com/showthre...d-In-Search-Of

[enishi1357]

I have the same error. I got this printer for free and I'm starting to think it's given to a recycling center not because the printer is outdated but because of this error and also makes sense it has rolls of filament left over so likely it's broken. If there's any update to this printer that would be great. I don't want to take apart the printer if possible.

[TommyDee]

Clogged nozzle more than likely. They use a visual sensor to see filament flow through the driver above the nozzle.

[enishi1357]

How do I get rid of the clog? Do a cold pull or just use a nozzle needle?

[Cubical]

I'd suggest removing the whole motor/nozzle assembly from the printer and disassembling it. When you remove the sensor board, be careful you don't loose the filament presence sensor, it just kind of slides onto 4 pins and is not held in place by anything. Also, use a marker to indicate which direction it goes as there's nothing to prevent it from being plugged in incorrectly. Then take the 4 bolts out of the drive section and separate it.

Next, pull the thermal fuse out of the cooling fins and unscrew the nozzle. I didn't need a wrench, just used my hands. If there's filament stuck in it you'll have to heat it up to pull it out. In my case, I just carefully plugged it back into the printer (w/o the motor assembly) and selected filament change so it would heat up. It's tricky because the head assembly moves around. Also, the left-most motor is what pushes on the left side travel-limit switch, so if you have that motor was removed, you'll want to push the microswitch by hand. You may also be able to heat it up carefully with a flame or heat gun.

To clear out the nozzle tip, I used a piece of guitar string. I realize not everybody's going to have that, but there's not to many things that are tiny enough to fit into that .35mm opening.

Once you've got the Teflon sleeve removed, take a piece of filament and see if it slides through the tube without resistance. On mine, the end of the sleeve that goes into the nozzle head was discolored and deformed (swollen) and the filament did not move easily through it. Best would be to replace it with a new piece of Teflon tubing (2mm ID / 4mm OD) but if you don't have it handy you can also use a small drill to ream it out.

When you put the nozzle back on, just finger tight, the threads are delicate and will snap off if you overtighten. When you put the drive assembly back together, put a piece of filament into the drive rollers so it has proper gap. If the gap is too tight it will cause too much resistance and the motor may not be able to turn reliably.

Also as a little helpful tip -- I used a Sharpie marker and made little marks on the stepper motor shafts of each extruder motor. That way I could easily see if the motor was turning forward/backwark/ or skipping because of a jam/clog. Also, if it's skipping because of a jam or clog you'll hear the motor bumping as it tries to push the filament but can't.

[enishi1357]

Well I cleared the piece of filament stuck and it still has that error. Maybe the other two extruders have filament stuck in it but I didn't see any from the extruder hole and pretty sure the end of the roll of filaments are not breakage so prob did not break during the unloading. My guess is the previous owner did everything and couldn't clear the error and decided to just toss it. When I have more time I will take a gander but prob a long while since I have eight printers on standby.

[TommyDee]

Worth a shot.