How to make sure your 3D printer won't catch fire!

Basic thermal protection is a feature that has been available in the standard 3D printer firmwares for a long time and it does a great job of protecting its heater elements when the temperature readings stop making sense. But as it turns out, some manufacturers don't bother to test that they are actually working. So here's how you can test you own machine - it only takes a couple of minutes!

Read the article to this video here:

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[tyttuut]

My printer doesn't have any legs, so I don't need to worry about it running away. The hotend sure does make a lot of smoke though.

[ucirello]

I'm pretty confident that this is one of those videos you make that is going to age very well and be useful for years to come.

[DMusketeers]

Love your radio station choices! Love the analogy for thermal run away! Glad to see a video on this! The industry needs more awareness!

[KennethTanFotografie]

I ( Couch..Finally) unpacked my Replicape today and started installing the firmware on the Beaglebone. During the upgrade I watched this video. Found it one of the "Share directy to friends" type.
Guess what the first warning/Error message was, Octoprint gave me after the initial install:
"MCU 'host' shutdown: ADC out of range - This generally occurs when a heater temperature exceeds."

Just having seen your video, this made me smile, as now I knew the reason, I had nothing connected yet to the Replicape and the software reported a temperature problem. Perfect Timing of your video.

[VAB]

I bought my first FDM printer for only $119. It is Mega Zero from Anycubic, Thermal runaway control in this is working so well that even when I had my thermistor just bit out from its appropriate spot, making it measure a bit less in temperature rise than the printer expected while heating up the hot-end, it shows thermal runaway error. I guess every brand has its own flaws in their printers. I’m just glad it is the other way around in mine. By the way your videos are great Tom, very professional and helpful. Thanks for making them. Keep it up!

[justinmoritz]

These thumbnails have leveled up recently 😆

[AndrewSink]

Perfect analogy for thermal runaway, and those are some top-notch compositing skills! 😂

[shadow]

Thank you for this. I got in to a discussion on the reddit about how the Voxel isn't safe because of this. But people always retorted with it can be fixed in 5min with a firmware flash. Which is true, but most people aren't going to be aware of it as way too many YouTube/online reviews just don't mention it so a buyer who just watches those reviews would not know about this issue.

[nathanwatrous]

This is a good PSA for anyone with a 3D Printer. Keep up the good work!

[andrewm]

Its wonderful to see this being bought up! Imo should be minimum standard for a consumer printers to have at-least thermal run away protection. I have a modified cr-10s that has thermal run away protection on a 240v heated bed with a thermal fuse and a seperate earth wire attached to the bed and ssr. I still have it in a aluminium and cement board box with smoke alarm and don’t leave it un attended

[thedarkknight]

There should be a list of printer models detailing which of those 3 thermal runaway tests they passed.

[delscoville]

I've checked my Ender 3 v2 when I got it, and checked it again after upgrading to Jyer's firmware. I also replaced the hot end with all-metal, as to not have a chance of any fumes from a burning PTFE tube.

[objection_your_honor]

This is why, as soon as I got my Anet A6 2 years ago, I chucked the electronics out and put my trusty Arduino Mega + Marlin + RAMPS 1.4.
Sometimes I forget the printer is not powered by mains but the electronics is still powered by the USB port, and I try to heat the nozzle, I get the thermal run away message.
Good to know it works. If I'm not mistaken, Octoprint also has thermal runaway feature built in.

[LimpiezasMyG]

thanks for doing a concise video and not speaking nonsense to just fill the 10 min for max youtube algorithm love

[panasananas]

Hi Thomas,
Great and useful info. But there is additional one very tricky situation: shorted/broken heater mosfet.

If your mosfet will be broken it will become like a simple jumper and not switch anymore. And if even Marlin firmware will notice that something wrong it will not help, because after switching ON printer 12/24v from PSU will appear immediately at heater.
As solution it could be used master relay that will cut off completely PSU from AC.
P/S I Am owner of MK3s, and I ask these question of their hotline, so they say that it is not recommended to keep printer alone because of these :). And of course MK3s do not have master relay/master mosfet.
P/S P/S I am repair engineer at factory and all new modern certified equipment has this master relay to prevent fire or health hazards.

[TotoGuy-Original]

This is relevant even today so many people getting 3d printers now and most of them dont know anything about this sort of thing

[filanfyretracker]

"honest officer I could not have been speeding, my car was clearly reading -20"

[BigDan]

A better level of protection is the octoprint plugin for the TP link smart plugs. You can add thermal runaway settings, i.e. if it drops below 5c or goes above 300 for example it will cut power to the printer completely, not relying on the printer's software.

[randomuser]

"The printer may damage itself or the environment it is in." Someone's been learning from air force incident report writers.

[hyprodimus]

Thanks for showing this. I just got an Aquila X2, and it passed all 3 tests.
H32 with firmware v5.1.5