Air printing. It appears every time.

[mathdesign]

Thanks you for reply.

" 1. Make sure you're using the latest firmware. pull the drive block off the extruder and make sure the drive gear is 4.9mm up the shaft. clean any filament off the drive gear. put the drive block back on. When you put it back on, press on it so you're pressing it towards the gear to make the tension tighter."

I use the latest firmware. and extruder assembled correctly.
But i can't fix it.
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