Help with strange blobs in prints

I have sometimes strange blobs in prints, like in the image. They appear and dissapear randomly between prints, changing colors, temps, and even doing nothing at all. I dont know if they are caused by alterations in the filament quality or other thing. Can anyone help me to solve this issue? Thanks

Hi Thorn666, It looks too me like steam bubbles. You get it from poor quality filament or if its old and hasn't been kept in a sealed container.
Have you tried any other filament?
Thanks
Matt

Its a bq brand filament ( a spanish company) but i use to have better finish with esun. I will buy some esun and see what happens. I try to keep the filament in a box with desecant, but the spool im using its always on the printer.

I had the same issue with the german company "Das Filament" it was very tempting buying 1spool for 15€ (no shipping, I picked it up). I had it in a sealed container for about 4 weeks with dissecant.

When it was time to use the spool, I noticed the same problem (but not that extremely).

For my opinion there are 3 possible reasons that might complement eachother:

- Filament has sucked too much water from the air because of thr bad quality.

- seamposition set at random or neareston, the slicer will get you that spots if you did not slice and calibrate you Extruder stepps properly

- Over extrusion due to the bigger diameter of the moist filament or wrong extruder Steps in the config file.

I hope it helps

Cheers

Oh... And I recomend Formfutura filament. Their Filament is specially made for BuildTak since they developed it..

PLA, EasyWood, PETG and almost every PLA blend work without problems..

ive tried with esun pla with diferent temps and same result. sometimes it prints ok and other with blobs. i cant figure whats the difference. same g code file, sometimes ok, sometimes with blobs. anyone have any idea?