Retraction problem

[flyintyler 0]

Sometimes my printer filament gets stuck.  When I investigate I see a thick plug of plastic stuck in the end of the boden tube where it attaches to the hot end.  It looks as though a large amount of melted material is retracted into the tube and then cools to form a plug.  Is this a setting problem? how could there be so much melted material at the hot end that gets retracted into the tube? Thanks.

[SandervG 1,521]

Hi, 

 

it could be that your front fan may not be spinning (sufficiently) anymore. Could be a few strings of filament got stuck in between the blades. Alternatively, or perhaps simultaneously, it's also possible that the tip of your bowden tube is skewed (did you ever cut it?) or not inserted fully and there is a small gap between the bowden tube and the coupler where your filament can expand.