small blobs on corners / bubbles between layers

[nihilianth]

Hm just checked those 2 possible reasons. The filament starts curling a bit but then extrudes in a straight line (due to gravity I guess :P) I will try to clean it with some string today.
Do you think it's a good idea to soak the hot end (or just the nozzle) in acetone before trying to clean it with the string? Or is it better to just warm it up to say 200°C.

Also, is it possible that the bubbles started to form due to ABS filament getting moist over time? I am not using any air-tight containers or dessicant for my spools atm.

P.S. the filament doesn't click, but there is some steam (or mb water vapor? ) coming out of the nozzle when trying to extrude at 220°C

[Geoff]

Hm just checked those 2 possible reasons. The filament starts curling a bit but then extrudes in a straight line (due to gravity I guess :P) I will try to clean it with some string today.
Do you think it's a good idea to soak the hot end (or just the nozzle) in acetone before trying to clean it with the string? Or is it better to just warm it up to say 200°C.

Also, is it possible that the bubbles started to form due to ABS filament getting moist over time? I am not using any air-tight containers or dessicant for my spools atm.

P.S. the filament doesn't click, but there is some steam (or mb water vapor? ) coming out of the nozzle when trying to extrude at 220°C

That could be something in your nozzle then. If it curls to a side and forms a ball, and when gravity takes over the ball drops and it forms another ball etc... this is a blockage.

No, no acetone really required, 200c is too low to flush any residual ABS. Warm it up to 250c and cook the gunk out. Mixing ABS and PLA will cause this or just PLA itself has a habit I find of getting clogged in the nozzle. If you don't have something to poke it out, just heat it up and let it get really hot and linger at 250, then feed a tonne of filament through.