by orcinus » Wed Jul 17, 2013 2:34 pm
When it rains...
Before the V-wheel, i had trouble with extrusion stopping after a random number of minutes, so i had to dismantle the hotend and extruder, replace the thermal barrier (SS tube), clean out the nozzle etc. Then the V-wheel cracked.
And then, yesterday, the X axis ground to a halt mid-print with a really REALLY nasty sound that rattled the whole table.
Since i've just bumped the PSU voltage up a tiny bit (1.5V), my panic-thought was "oh no, i've fried the driver". Which makes no sense, of course. But hey, panic. So i've replaced the driver with a spare one and - same thing. X stepper just rattles and shudders. So my next illogical troubleshooting thought is "oh no, one of the Atmega pins is fried". And i try plugging the stepper into a different socket altogether. Same deal. So i take out a spare stepper (yes, i'm a spare hoarder, i know) and hook it up and... same deal.
This is the point where it finally managed to get through to my brain that stepper moving back and forth very quickly means one of the coils is disconnected. So i check the connectors (and they're visually fine) and i do a continuity check and - lo and behold - it turns out one of the wires snapped.
No idea how. Bizarre.