Ideas for detection of filament outages and how to handle them (automatically, UM2)

[NBroenner 7]

Hallo,

I would like to discuss some ways to detect "out-of-filament" situations. This thread should be about the hardware and afterwards about the needed fixes to the firmware. The hardware addons could be done on nearly all ultimakers, but I would like to address the UM2 primarly, since I only own a UM2 and no UMO or similar (If these addons appeal to anyone with an UMO and he/she is willing to do the changes to the firmware, feel free to use it ). Therefore I would suggest the @tinkergnome firmware (https://github.com/TinkerGnome/Ultimaker2Marlin) as a good starting point. This thread continues the discussions of this thread http://ultimaker.com/en/community/view/7436-more-information-during-print .

So here are my first thoughts:

 

• The easiest solution would be a sensor like the reprap opto endstop electronic (http://www.reprap.org/wiki/Gen7_Endstop_1.3.1+) in combination with a housing like http://www.thingiverse.com/thing:744006. The opto endstop is even easier to address than the sensor used with this housing, since it only knows two states on / off.
  
• Another issue could be clogs. These could be addressed by an rotary encoder (http://playground.arduino.cc/Main/RotaryEncoders). This could be incorporated in the firmware parft of the stepper motors to control their progress. If they do not report changes but the stepper motors have been commanded to move this could indicate a clog.
  
• Another more complex solution could be to have two rolls of filament ready. If the first runs out, then the printer switches over to the next roll. There are different approaches for these: e.g. the cyclops from e3d (http://e3d-online.com/Cyclops), but this one requires a lot of adaption and is only for 1,75 mm filament at the moment. I would suggest another approach: install a second feeder for the reload. In the bowden a joint (similar to this one: http://www.thingiverse.com/thing:330757) has to be installed. And the opto endstop sensor can be used to detect the filament outage. If the sensor detects the outage of filament, the printer pauses and switches every signal from extruder 1 to extruder 2. There should be a starting procedure in order to avoid blobs of plastic after the switch.
  

 

What do you think ? What else solutions would you recommend ?

Thanks,

Nils

[NBroenner 7]

Hallo,

does nobody have any idea how to improve the out of filament handling ?

Regards,

Nils

[gpb01 23]

@NBroenner :

Can you read from HERE on ?

Guglielmo

[NBroenner 7]

Hi Guglielmo,

thank you very much. I am thinking on getting one of these tunnel sensors, too.

Regards,

Nils