In this instructable I show You how to load flexible filament. Some of Extruder not supporting flexible filament. Almost extruder design different, but working same technologies .
Normally in extruder there are two or three wheel, one is connected to stepper motor, push tightly towards hot end using support with other wheel and spring. PLA or ABS filaments are strong and it easy moves. But the flexible filament is smooth. It would not enter hot end for bellow reason
1. Large gap between pushing wheels.
2. Curvy part inside extruder.
3 . Long gap between wheel and hot end.
So if you watch this you will get idea and you may load and print flexible filament in any extruder.
This is normally happenings flexible filament loading
Loose this nut
adjust parallel (it work for some extruder if not working adjust like step3 )
Load flexible filament and adjust it straight. It should not any curves.
Rotate wheel . It should move towards hot end like picture 1.
Picture 2 happen if any above 3reason.
Make sure all position is correct and tight the nut. and
test it..all the best!
also you can check it in video