Is It Safe to Leave a 3D Printer Overnight?

Mario De Lio

Last Updated:

Disclosure: This post may contain affiliate links. We may receive compensation when you purchase via my links at no cost to you. See our disclosure for more information.

3D printer prints the form of molten plastic green.


  • Leaving a 3D printer overnight carries risks like fumes and fire hazards.
  • Extra safety measures can reduce risks but not eliminate them.
  • Noise reduction and monitoring tools can help if printing overnight.

Leaving your 3D printer running overnight can be risky as the heat generated by the hotend has the potential to start fires. Most manufacturers advise against leaving your 3D printer running overnight for safety reasons.

That being said, many people still choose to run their 3D printers unattended for extended periods. I myself have run 5 and 7-day prints, leaving my 3D printer unattended for several hours at a time.

In this article, I’ll cover the risks of leaving your printer running overnight, and essential safety precautions to minimize the risk of fire.

Is It Safe to Leave a 3D Printer Overnight?

A 3d printed low poly dog with Wooden pla and tree supports on the bed of a 3d printer
(Photo by Marcello/3D Print Mentor)

The short answer is that leaving a 3D printer overnight or unattended is risky. Although rare, components can overheat and start fires. Additionally, prints fail for a variety of reasons. And it’s incredibly disappointing to wake up to a failed print. Beyond the disappointment are the hours of wasted print time and the amount of wasted filament.

It’s easy to say that you shouldn’t leave a 3D printer overnight, but that’s not always possible.

Some prints take 8 or more hours to finish. I’ve run countless prints that take more than five days to complete.

With the right safety precautions, it is possible to minimize many of the risks associated with leaving your printer running unattended.

What Can Go Wrong?

A photo of a red pla 3d print that failed. The nozzle collided with the print and knocked it off the build plate resulting in spaghetti

Leaving your 3D printer on overnight can lead to several issues. One of the most serious problems is the risk of a fire hazard. 3D printers generate heat, and if the machine malfunctions, it can overheat.

This is called thermal runaway.

If not caught in time, this overheating can lead to a fire.

Another common problem is print failures. If a print dislodges from the bed or if the stepper motors skip, the print could end up a mess. In the worst case, the toolhead can collide with the bed or other parts, breaking delicate components.

Most home 3D printers don’t offer print failure detection. If your print fails, the printer will continue extruding filament, unaware that an issue has occurred. The result is wasted filament, costing you money.

Noise disruption can be another issue. But 3D printers can be quite loud, making it hard to sleep if you are nearby. Modern printers use silent stepper motors, but it’s common for the fans to create noise.

Using quieter models, a 3D printer enclosure, or soundproofing can help here, but it’s something to consider.

Preventive Safety Measures

A top down view of an upgraded Creality Ender 3 V3 KE in a fireproof enclosure

While it’s impossible to eliminate the risk of leaving your printer unattended, you can take safety precautions to keep your printer safe.

  1. Ensure Proper Maintenance: Regularly check your printer for any signs of wear and tear, loose wires, or malfunctioning components. Proper 3D printer maintenance keeps your machine in good condition and reduces the risk of accidents.
  2. Enable Thermal Runaway Protection: Ensure your printer’s firmware has thermal runaway protection enabled. This critical safety feature shuts down the printer if it detects abnormal temperature fluctuations. Most new 3D printers have it enabled by default. But it’s always good to check.
  3. Update Printer Firmware: Regularly update your printer’s firmware to the latest version. Updates often include important safety features and improvements that help prevent accidents.
  4. Proper Ventilation: Place your printer in a well-ventilated area, away from flammable materials. Good airflow helps dissipate heat and reduces the risk of fire.
  5. Monitor Remotely: Set up a camera to monitor your printer remotely. This way, you can check on the progress and spot any issues immediately. Note: You can install OctoPi on your Raspberry Pi to remotely monitor your 3D printer.
  6. Install Smoke Detectors: A smoke detector near your printing area provides an early warning in case of fire hazards.
  7. Keep a Fire Extinguisher Handy: Place a fire extinguisher near your printer. This way, you’ll be prepared to act quickly in case of a fire. You can also purchase automatic fire extinguishers, which suppress fires when they detect heat.
  8. Check the First Layer: Before leaving the printer unattended, ensure the first layer adheres properly to the print bed. If you notice an issue with the first layer, you can prevent most print failures by stopping the print to prevent wasting filament.
  9. Keep the Area Clean: Maintain a clean and organized printing area to minimize the risk of dust or debris causing accidental fires.
  10. Use a Fireproof Enclosure: Consider using a fireproof enclosure for your 3D printer. This adds an extra layer of protection by preventing any potential fire from spreading.

Article by

Mario De Lio

Ready to Improve Your Results?

Dive deep into the world of 3D printing with our exclusive newsletter. Get insider tips, hands-on reviews, and the latest news to improve your 3D printing.