Taz 5: Motor stops spinning -- no filament being fed to hot end


I’ve got an issue with my Taz 5 suddenly… It’ll print about 2mm tall worth of a print then all the sudden the herringbone gear and hobbed bolt stop spinning. I guess for whatever reason the stepper motor stops rotating.

I checked my small herringbone gear and made sure the little screw in the side was tightened… Restarted a print and same issue. I did notice that the small gear was sitting a bit “cock-eyed” in relation to the larger gear… but the teeth were locked together just fine and up until the 2mm point it spins the large gear just fine…

Piercet suggested that if it wasn’t the small gear then it could be a motor cable short, a failing motor coil or a failing control chip on the rambo board. Thus I am going to change the motor cable now since it came with 2 cable and see if it works from there… I am hoping it’s not the latter – not sure how that gets repaired.

Any other suggestions / sanity checks? I added a few pics…



Does this happen on the same model everytime? If so it could be an issue with the model itself.

It so happened that a long time ago I had printed the replacement herringbone gears (both large and small) in PLA. During the print the small herringbone gear was getting enough heat transfer (these were ABS prints) from the motor that it would reach a melting point mid print then the motor shaft would basically spin inside the small gear without rotating it. When I would kill the print and cuss the machine it probably cooled back down/re-solidified around the motor shaft and once I started a new print it would work up until the point where it reached melting point again.

Moral of the story: don’t use PLA for any of your extruder head parts! Unless it’s the idler arm latch or something…

I printed replacement gears in ABS on my Taz 6, replaced them on the 5 and it’s been printing fine now