SoliForum - 3D Printing Community — How hot did it have to get for this to happen?

Re: How hot did it have to get for this to happen?

2015-12-24T21:48:30Z

I'd guess a case of hung firmware then. Can happen from something as random as a power blip.

Re: How hot did it have to get for this to happen?

2015-12-24T21:21:52Z

Replaced the heater block with one from my spares box, installed new thermistor, and dug up a used but working 24 volt heater (yes they are 40W according to the package). Opened up the bottom of the printer and gave the board a close examination, did't see anything obvious like a burnt component or trace so I powered it up and everything appears to be working as it should. As soon as the bed gets to temp I'm going to run a test print to see how it goes but you can bet I'm going to stand there and watch the entire print just in case!

I checked the stats in the Repetier firmware and this printer has run for a total of 2180 hours with close to 21 kilometers of filament having been extruded in that time, this is the first instance of it acting up and I hope the last, fingers crossed, about to click Start Print...

Re: How hot did it have to get for this to happen?

2015-12-24T16:59:48Z

Oh gotcha, I misunderstood. They're 40w units then most likely, which top out at 550C or so.

Re: How hot did it have to get for this to happen?

2015-12-24T15:06:19Z

The heaters are (were) the correct 24 volt parts from the printer manufacturer though I have no clue as to what watt rating they are. I've seen 12 volt units hooked to 24 volts, yup the warm up times are impressive!

Re: How hot did it have to get for this to happen?

2015-12-24T04:32:02Z

25w heaters become 100w heaters when the voltage is doubled. I bet you had some sensational warmup times, though!

Re: How hot did it have to get for this to happen?

2015-12-24T03:54:24Z

Ahhhh.... since this machine uses 24 volt power I didn't swap the heaters when I did the switch, left the fairly new 24 volt units that were already installed in the previous dual print head setup. I originally intended to install the Chimera on a different printer so didn't request 24 volt heaters when I ordered it, wound up ordering another for that other printer after I used this one doing the conversion to 1.75 filament from 3.0mm.

Guess I'll be ordering some new 24 volt lower wattage heaters along with whatever else I need to get the beast back up and running.

Re: How hot did it have to get for this to happen?

2015-12-24T03:33:09Z

It has to get to around 550C. Possible with a 40w heater, not possible with the 25/30w heater E3D ships by default unless it is being run at more than the rated voltage.

My guess would be hung firmware/failed MOSFET.

Re: How hot did it have to get for this to happen?

2015-12-24T02:31:47Z

That looks like a runaway heater to me. The thermistor was no longer sensing accurate temperatures which led to an increase of temperature.

I'm glad you, your family, and you home are ok!

How hot did it have to get for this to happen?

2015-12-24T02:15:41Z

Went upstairs for a quick bite to eat shortly after starting a print job, just as I was finishing up caught a whiff of something odd, came back downstairs to find this...

Printer has been running with the Chimera since the first or second batch made it to the USA and up to now no problems at all. Controller is a Azteeg X3 Pro, best guess is something on the board smoked allowing the hot end to go into thermal runaway, quite surprised to find the heater block becoming a puddle of slag, how hot does it have to get to melt aluminum!?!?!?!

Now I have to haul it out of the enclosure and open the bottom to check out the controller, hope I don't need to print anything larger than the SD3 can handle till I get this sorted.