Nozzle clogging is one major issue with FDM 3D Printers. When nozzle gets clogged, material won’t get extruded. There are multiple reasons for nozzle clogging. Nozzle clogging can be completely avoided if some preventive maintenance measures are taken. Below are certain reasons for clogging of the nozzle
(a) Inserting a new filament that has lower temperature requirement without cleaning out the nozzle completely
(b) Dusty filaments
(c) Filament stripping in the extruder gear and the filament left in the nozzle
How to unclog the nozzle: There are multiple ways to unclog the nozzle. Below is the detailed explanation of these various ways to unclog the nozzle
(a) Brass wire brush – Use a brass wire brush to clean off any debris / remains from the nozzle. This will prime up the nozzle by removing unwanted particles. Use only brass wire brush and don’t use steel wire brush as steel wire brush can cause damage to the nozzle.
(b) Acetone bath – Thermoplastics dissolve well in Acetone. So cleaning the nozzle with acetone bath helps remove unwanted particles and unclogs the nozzle. For the acetone bath, first heat up the nozzle to the print temperature of the last material used and then use a wrench to detach the nozzle from heater block. Once detached, keep the nozzle in acetone liquid overnight. This works very well for ABS. If there are other types of filaments, then use heat gun to melt out the remaining filament.
(c) Acupuncture Needle – One other approach to clean nozzle is to use acupuncture needle. Preheat the nozzle to the print temperature of the last nozzle you are printing with and gently insert the acupuncture needle up through the nozzle, push and pull the needle through nozzle for few times to clean the nozzle.
(d) Cleaning Filament – Heat the nozzle up-to 250 degrees centigrade and push the cleaning filament through nozzle until you don’t see any of the old filament coming from the nozzle, then pull out the filament from nozzle and heat it once again to remove the remaining filament from the nozzle and clean the nozzle.