MakerGear M2 24V V4 Hotend Randomly Stops/Pauses Mid-Print

[insta]

Likely a loose wire around the thermistor. It's a fun one to track down -- usually you just get a replacement.

[w22]

Thanks insta. When you say replacement, what exactly am I replacing and how did this happen? My printer looks like I just bought it today and I've never moved it.

UPDATE

I've been attempting to replace the thermistor but it is incredibly jammed in the extruder and the side screws won't budge either. I see the tip of the thermistor turning the nozzle upside down but it's not budging.

UPDATE

I replaced the thermistor perfectly and made sure everything was screwed back the way it originally was (set screws, extruder screw, fan screws, etc). I noticed I get the 0 degrees Celsius MINTEMP M999 to restart Extruder Temperature failure between the 40 and 51 x-axis degrees. All degrees before are a steady reading of 23 degrees celsius as is the heating bed (which is always at 23 when resting like normal).

Could it be the wiring all the way from the heater to the motherboard at the bottom that's all zip tied up the whole spine of the printer?

[Tim]

Could it be the wiring all the way from the heater to the motherboard at the bottom that's all zip tied up the whole spine of the printer?

Seems unlikely, but with most of the alternatives ruled out, maybe not so much. At least it's pretty easy to check by running a different set of wires from the board to the extruder thermistor; doesn't have to be more than a hack job to prove the point (or not).

[w22]

Woohoo! Thank you all for your support. MakerGear support was Phenomenal and helped me through the whole process. It absolutely was the thermistor wiring running from the printing nozzle all the way to the motherboard at the base. Y'all are nothing but amazing!

[Tim]

Woohoo! Thank you all for your support. MakerGear support was Phenomenal and helped me through the whole process. It absolutely was the thermistor wiring running from the printing nozzle all the way to the motherboard at the base. Y'all are nothing but amazing!

Nice to know that you have it all back running again!

Now I'm beginning to have a lot of questions about thermistors. I have been seeing some instantaneous jumps in my temperature readings, like one or two bad readings during an entire print. So now I'm trying to figure out. . . is this normal? Do thermistors and/or their wiring go bad at a pretty high rate (they do operatate under harsh conditions) compared to other components? Is a one-off reading really a sign of a failing thermistor, or does it mean that the code on the receiving end should be rejecting outlier readings? If anybody has any enlightening information, I'm all ears. . .

[ednisley]

Do thermistors and/or their wiring go bad at a pretty high rate

The problem isn't the thermistor itself, but that those hair-fine wires suffer far too much mechanical stress: they're not firmly anchored outside the thermistor, so all the flex from that big bundle of wires translates directly to the hard joint at the thermistor body. Shake the bundle a little bit on every X-axis move, the strain accumulates at that joint, and, after a while, the wire is passing current hand-to-hand along a few atoms.

On the whole, the thermistors work fine and last a long time, but some of 'em take a real beating. Removing & replacing the hot end, fiddling with the the nozzle, clearing jams: any movement flexes the wiring more than usual.

Is a one-off reading really a sign of a failing thermistor

IIRC, a single thermistor temperature report comes from many (16?) averaged ADC samples, so a "weird" reading means something's going badly wrong down in the engine room. Best to stock up on spares while you have the chance!

[Tim]

Removing & replacing the hot end, fiddling with the the nozzle, clearing jams: any movement flexes the wiring more than usual.

Completely taking apart my M2 and putting it back together a number of times over the course of the twin independent extruder modification must have taken its toll, and I guess I should not be surprised.

Best to stock up on spares while you have the chance!

Wise idea, definitely I will do that.