Crazy feeder when changing material

[RonanB 4]

Hi !

I post here because I had a problem and i want to share it with you.

When i was changing the material on the um2 extended, the motor go crazy.

 

• when removing the material, the motor of the feeder remove the material but when the material was removed the motor didn't stop turning and it was turning irregularly (normal speed 2 sec, fast 1 sec , ...)
  I thought it was ok so i continue manipulation.
  
• During inserting the material, the motor of the feeder does the same in the other way. Also, normally the motor slow down when the filament get close with the nozzle but this time it didn't. So the printer was extruding the filament with the same pattern (normal speed 2 sec, fast 1 sec , ...) causing intense grinding.
  
• I shut down the printer, restaure factory settings and it solve it.
  

 

Any idea why it happens ? I think it's because I used a very old cura (with hexa pattern) to generate Gcode for the last print and it make the printer crazy :(