Thermal runaway is one of the most dangerous errors that can occur during 3D printing. Simply put, it refers to the situation in which a 3D printer heats up to extremely high temperatures and can’t stop. In this scenario, it’s not uncommon for the printer to catch fire.
Thermal runaway can happen for a host of different reasons, but the main one is probably your temperature sensor, the thermistor, is misaligned. Unable to properly sense the current nozzle or bed temperature, a firmware will continue to raise the heat in order to reach the target temperature.
In this article, we’ll discuss how you can prevent thermal runaway both through your printer’s firmware and other general safety practices. We’ll also give you a step-by-step guide on how to test whether your 3D printer’s thermal runaway protection is activated and working.
Thermal runaway is a very scary possibility, but there are ways to protect your printer from damage. The main way to protect your printer is to make sure that thermal runaway protection is activated in your printer’s firmware. The firmware feature doesn’t prevent thermal runaway, but it does attempt to stop a printer’s overheating in its tracks.
Basically, thermal runaway protection aborts a print when there’s something fishy about the thermistor’s readings. To be more specific, the feature detects that the value has been significantly less than expected for an extended period of time.
The firmware in most 3D printers, notably in Prusa and MakerBot printers, have thermal runaway protection activated by default. The popular firmware group Marlin has a lot of thermal runaway protection features, too.
Overall, thermal runaway protection in your 3D printer’s firmware is vital for lowering the risk of fires, damage to your printer, and damage to the surrounding area while printing.
How do you know if the thermal runaway protection in your printer’s firmware is working properly? The best way is to run a test. In this section, we’ll look at a way to do just that. To start, you’ll need the following materials:
Before you start, make sure your printer is turned on, the heat block is at room temperature, and nothing is being heated. Once you’ve checked these items, the steps are as follows:
If your printer didn’t bring up an error or stop the print and all heating, that means thermal runaway protection isn’t activated in your printer’s firmware. Don’t worry, though, you can add it to your firmware, or the easier option, change your firmware to one that does have the protection activated, like Marlin.
It’s always good to follow safety practices. Here are some additional fire safety tips that’ll help reduce the risks of fire and fire damage.
Overall, you really want to keep your printer as safe as it can be, whether that means installing new firmware or moving all your post-processing chemicals. It’s definitely worth it: Safety should be your number one priority.
License: The text of "Thermal Runaway (3D Printer) – Simply Explained" by All3DP is licensed under a Creative Commons Attribution 4.0 International License.