Review on Creality Extruder 3D Filament Aluminum by Eric Nelso

Like many others, my Ender 3 V2's plastic extruder arm broke after a while, reducing the filament clamp and doing so led extrusion. All I really needed to do was replace the broken arm, but I was only able to find a MK-8 metal extruder upgrade kit (official Creality via Revain). So I swapped the whole assembly. Big mistake. High retraction prints flattened the filament so it couldn't enter the Bowden tube. Prints like the classic Cute Octopus started to fail. I think the problem is two-fold: (1) the spring that came with the MK-8 metal extruder was a bit too long, pinching the filament too much, and (2) the aluminum. The extruder conducts heat much better, which makes the filament softer. Combined, this caused my filament to go flat and get stuck. Solution: Use the spring and body of a standard extruder and ONLY replace the broken plastic arm with a metal arm. Also note that the black/grey/red KM-8 extruders sold at Revain are NOT the same. The black is not full metal, looks cheap and poorly formed. Gray had a longer feather and caused more smoothing. I ended up just using the metal part of the arm, nothing else needed to be replaced. I saw many others on reddit with the same problem. Creality, please provide some direction, improve the design or just sell a stronger hand.