Printer stops midprint "Heating head", then shoots out to the edge
I started having this problem today morning, and ever since all the my attempted prints have failed the same way. I start the print, first layer goes down as expected, then on the second or third layer the printer just stops for 2 or 3 seconds, displaying "Heating printer head", then carries on but either have a major layer shift, or completely shoots to the edge of the bed, keeps grinding there as it would try to keep moving to that direction, then turns around and keeps printing again.
Here is the problem: when the printer stops and displayes this message, the temps are perfect, not even 1 degree below where they should. Also when print restarts after mentioned few seconds, how come the printer completely forgets it's position? It even forgets the endpoints, as it would try to go even after it bumps into the edge of the printer, and then it keeps grinding for a second, then turns around.
I have included two pictures about these failed prints, have a look. First layer fine, then second or third layer you can see a blob where the head stopped, then a major layer shift on the first print, as I wasn't there to catch it immediately. On second picture I was sitting right next to it, so I stopped it immediately when this thing happened.
Oh and want to mention that after the first failed print I changed the temperature sensor unit as I had a spare one from a previous trouble shooting adventure (unrelated to this one), and the same thing keeps happening with this new one as well, so the sensor can't be the culprit. Is it possible that the control board is toast in my printer? I just can't think of anything else. I have printed roughly 1500 hours with the printer, and I would say about 400 hours from this was printing ABS in an enclosure (to combat warping). I would still find it disappointing if this could cause the failure of the board. Any other ideas?
What firmware version are you running ? There is a known issue with the firmware and the filament sensor that causes this. The initial work around is to turn off the filament sensor.
Not sure if its fixed in a release yet (or if it is which one its in).
Oh wow, I really hope it will be an easy fix then. The firmware on my printer is 3.6.0-2069. I tried to upgrade it with a newer firmware, but it didn't work, said checksum error or something like that, and in fact almost bricked my printer. This current version of firmware isn't original either, I upgraded it, had a similar error during update, but for some miracle after a few minutes my printer recovered somehow.
Needless to say after all these experiences I am never going to do a firmware update, as I am almost certain I would have a brick instead of a 3D printer after my next attempt.
And funny thing is I never used to use the filament sensor, I just switched it on recently. Will switch it off tomorrow and see if that solves the issue.
Turns out you were absolutely right. I have disabled the filament sensor, and have been printing without any issues ever since.
It's extremely annoying though, as now there is one more thing I have to keep my eye on (to not run out of filament mid-print). And thanks to the dodgy firmware update I am too afraid to update it to the newest firmware, so now I am stuck with a £700 printer that effectively doesn't have a filament sensor. Not impressed.