HOW TO diagnose underextrusion

AlexPasseno

when dealing with underextrusion there are a few things you have to ask yourself, "did i make any large changes to how my filament feeds into the hotend recently?" "how long has this filament been sitting out?" "am i printing with composite filaments?" "Does the extruder arm feel tight enough?" or "have i recently swapped from a high temp material to a low temp material?"

If you made a large change to your extruder setup (IE. swapped to a direct drive from a bowden style or vise versa) you will probably need to do an estep calibration

All filament has a shelf life to it that is highly dependent on ambient moisture my general rule of thumb is about 2-3 months out in open air for pla, but you can check to see if the pla has gone bad early, if you bend an inch or two of filament at the end of the reel and it bends, then its still good, if it snaps the filaments probably gone bad.

if you are printing with composite materials (carbon fiber, wood, glitter) then there is a good chance you have a partial clog, the easy fix is to replace the nozzle and call it a day but the right fix is to take a small acupuncture needle and stick it through the tip while the nozzle is heated (be careful! that nozzle WILL be under pressure and releasing that clog sometimes causes it to shoot out)

the extruder arm is the lever you have to push down right where you feed your filament in, this arm is typically made of an injection molded plastic which will eventually just shatter! upgrading to a metal extruder will usually fix this issue (sku 135723 for most printers)

best practice from swapping from a high temp material to a low temp material is to run a bit of purge filament through, however in a pinch you can heat your nozzle to ~10 degrees higher than the material you were just printing with it and shove some of the lower temp material through untill it runs through clean (do note DO NOT EXCEED 260 DEGREES AND PUSH PLA THROUGH this will carbonize your pla and that is a pain to clean up and will require purge/cleaning filament to fix)