CR10S-PRO extruder

The extruder is sturdy, but has some design flaws:
1. The idler gear needs to have its base filed and a steel washer under it. else it will eat into the aluminium of the arm.
2. The filament exit has too much space in the nozzle cavity. You need to cut a small section of teflon tube to fit in here to limit the space the filament has to bend.
3. The grub screws are designed for a flat sided shaft, so if your stepper shaft is round, file a flat on it or the grub screw will not go in far enough to clear the mechanism.