Broken extruder

[PcS]

This was an easy to diagnose problem !!! Lol

[jimc]

Man there have been a few cases if this over the past few mos. i dont even get how the stepper has enough torque to do that. The issue popped up out of nowhere though so it has to be a production issue with kysan....i would think.

[ednisley]

how the stepper has enough torque to do that

A closer view of the shaft:

PcS - Broken M2 extruder motor shaft - detail.jpg (140.55 KiB) Viewed 4826 times

That dark spot on the motor end of the shaft (at about 10 o'clock) might show a flaw in the metal; it matches up with similar mark on the stub. The rest of the fractures look like what you'd get in case-hardened steel.

Given the bazillion snap-reverse cycles we ask of those poor motors, it's amazing they last as long as they do.

a production issue with kysan

Or whoever makes their shafts: that's a hot potato for the QC folks.

[PcS]

I have done a lot of long prints lately with lots of retraction . 30 hr back to back .