Most nozzle jams occur after switching materials, or after suspending use. So how to clean up the nozzle, in order to avoid the nozzle clogging?
Switching materials: Another cause of nozzle jams is not cleaning your nozzle in between material transitions. For example, if you 3D printed PLA and want to switch to ABS, you should always clean the nozzle in between. There are a few techniques for cleaning the nozzle in between filament changes to remove residue, including cold pulling or using a wire brush to remove residue from the outside of the hot end.
Needle: This method is one of the easiest ways to remove debris from inside the 3D printer nozzle. Start by heating the hot end to the temperature that corresponds to the last material you 3D printed. Then, use a fine needle or wire, such as an acupuncture needle or a fine steel guitar string, to gently poke upwards through the nozzle hole. This should break up the filament debris that is blocking the nozzle so that it can be easily extruded.