¶ 1. Heat the nozzle to 240° and use a silver needle to clean the nozzle
¶ 2. If the nozzle is not clogged, check if there is any filament material in the inner throat, if there is, you can use tools to clean it
¶ 3. If the nozzle and throat are not clogged, check the lower guide tube
Check the guide tube for clogging!
¶ 4. Disassemble the extruder and check if the 17-tooth main wheel is loose. If there is looseness you can contact the after-sales mailbox to deal with it: service@flsund3d.com
¶ Video link for checking nozzles, throat, lower guide tube for clogged:
https://www.youtube.com/watch?v=rvOFmBPcwwE