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Extruder not working

Posted: Tue Oct 20, 2015 11:58 am
by Sherry
If you encounter with the problem on extruders not working, please consider those case.

1) Checking if the extruder temperature has reached the preset temperature, the lowest working temperature for extruder is 175°set up in the firmware. When heating, if it do not reach the temperature you set up(over 175°),the extruder will be still at the left hand corner(home position) rather than moving to the center of print bed.

2) if the nozzle has reached the temperature you set up, and x,y,z stepper motors work correctly, but filament does not come out from the extruder . I have some tips for you


If the motor do not rotate, maybe those parts or components have glitch.

①The subdivision of the stepper motor is 1/16. It means you need to plug all jumper caps.

②Please see if the stepper motor or motor cable is broken. You can verify them by plugging them to another working motor connector such as x or y.

③Please see if the stepper driver board of extruder is broken. Simple test: swap the extruder driver with a good driver. Then check if extruder can work well or not.
Besides, the voltage between potentiometer and GND is 0.8V-1.2V. if it less than 0.8V,you should increase it by tightening the potentiometer(screw)
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Symptoms of not enough current are skipping steps and poor microstepping linearity. Too much current will cause the motor or the driver to overheat. When the driver overheats it shuts down for a few seconds and then restarts again when it cools. This makes the motor twitch when it is stationary and pause during motion.
④In rare case, the motor do not receive signal that causing stepper motor not running
In this case, one of reason is you do not burn correct firmware or the firmware has bug. You can reinstall the firmware in this link.
viewtopic.php?f=20&t=17046
Another reason is some pins near extruder motor are shorted out.

If the extruder motor can rotate, but hear click noise or the extruder motor move in a narrow range. In this case, please check whether the gap between idler wheel and gear are too large and the pressure is too small to drive the filament. you can refer to this link.
viewtopic.php?f=19&t=18507
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Tips:
1.You have to make sure the filament has entered the throat rod or it will also make click noise.

The method to verify if the nozzle is clogged.
You can verify if the nozzle is clogged by following ways.
Heating the extruder to 190°-210°(PLA),or 230°-250°(ABS).When finish heating, please press one end of lever with one hand, and extrude filament with force with another hand. If filament could not come out from nozzle, the nozzle is clogged.

Factors causing nozzle clogging.
The temperature you set up for extruder is not high enough.
PLA: 190°-210°
ABS:230°-250°
The gap between nozzle tip and print bed surface is not high enough. The best distance fot the gap is the thickness of an A4 paper. If the nozzle touch the print bed tightly without room. It is easily clogged.
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If the nozzle is clogged indeed, please clean it with drill(needle).
1. Stopping the nozzle with repetier host, then move nozzle away from printing object.
2. Heating extruder (PLA190°-210°,ABS 230°-250°),pull out filament from nozzle to prevent further clog.
3. Remove the cold end, just leave the nozzle.
3. Clean surplus jam with the needle, please be careful and gentle as there is a tube in nozzle. Please do not damage the tube when cleaning jam .
4. Assemble the fan, heatsink and extruder motor, replug the filament to nozzle.
5.Here are some videos showing how to clean the jam, please check this post:
viewtopic.php?f=19&t=16414
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Re: Extruder not working

Posted: Thu Feb 18, 2016 4:20 am
by Stunzasr20
Hi
I am having issue 1, the extruder is not reaching the minimum temperature. It only gets to 90/200. I have verified the stepper motor actually works by plugging it into my y axis and manually moving the axis with the LCD screen and knob.i also have confirmed the voltage to be at least 0.8V on all four drivers. This is a new setup and have never had this working yet. Board is Sanguinololu and printer is Prusa i3a.
Are you able to offer any suggestions to solve this issue.

Re: Extruder not working

Posted: Thu Feb 18, 2016 4:37 pm
by Mark
I just thonght of the resistance of the bed and heaters, are they all proper? you can check this link below:
http://www.geeetech.com/forum/viewtopic ... 19&t=17039
And when heated up the heaters, is the PSU output still be 12V? if it drops too much then the PSU might be faulty.

Re: Extruder not working

Posted: Thu Feb 18, 2016 6:53 pm
by Stunzasr20
Hi Mark
I have checked the resistance in both the extruder and heatbed and all agrees with your test. With the exception that when i turn on the printer the thermistor for the headbed appears to be no good. It reads 45/0 when at idle, then when i plug laptop in via usb port and turn on the extruder and the heatbed via manual control through repitier host the result after say 5 mins is 90/200 46/95.
The voltage is still constant throughout all of the above processes 12.07V, but I am starting to run out of ideas. Could the PSU be causing these issues?

Also i note that the resistance at room temperature of the heatbed thermistor is 4.4 Kohm. When you say it is 100K , is that actually 100Kohm?

Re: Extruder not working

Posted: Thu Feb 18, 2016 8:36 pm
by Mark
quite weird...yeah I remember mine is about 117K when at room temperature. Don't know what's the problem is now...maybe post some pictures to check the wirings and others things, see if we missed anything..

Re: Extruder not working

Posted: Thu Feb 18, 2016 9:00 pm
by Stunzasr20
I have followed the instructions to the best of my ability and believe that I have covered the things that appear necessary. I can only think to try a firmware update (did one about 2 months ago) and see if that changes anything. I feel like I can't check anymore than I have.
For that matter could there be a setting in the config somewhere that is giving such problem.

Re: Extruder not working

Posted: Thu Feb 18, 2016 9:10 pm
by Mark
can't remember such settings...but if you use the original firmware, then it won't be a problem.

Re: Extruder not working

Posted: Fri Feb 19, 2016 3:26 pm
by Stunzasr20
Hi Mark
I have re-uploaded the firmware however it made no difference to the heating of the extruder, it still only reached 93. Attached is a picture. I have spent so much time trying to solve such an issue. All steppers work, so all i can say it is either, The PSU, the mainboard, the heatbet thermistor and or the LCD (all the electronic bits that communicate with each other). I have already placed a mainboard in this priinter. I am starting to loose all hope of this working at all, Please help

Re: Extruder not working

Posted: Sun May 08, 2016 10:40 pm
by Fer8973
Hi,
I need help please, finally my 3D printer is working, but I have a problem with the amount of filament that is been extruded. It is not enogh. There is a significant change if I use my hand to press filament into the extruder. My 3D uses the MK8 extruder, I tried all you explain in this post but the potentiometer adjust. I don't find where the potentiometer screw is. Thanks.

Re: Extruder not working

Posted: Mon May 09, 2016 2:42 pm
by Admin
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it is here