If you can spend a few hundred bucks on a 3D printer and some filament, you can afford to spend a little on a few upgrades to ensure that your hobby is a safe one.
While there’s no need to be alarmed, it’s better to be over-prepared than not prepared at all.
Your 3D printer is a fire hazard
Though the risk of fire is small
Like most other appliances that you own, the chance that your 3D printer will spontaneously combust and cause you harm is slim. At the same time, there are parts of your 3D printer that present a real fire hazard. Perhaps the most obvious of these is the nozzle, which can reach temperatures of around 300ºC or higher.
Thermal runaway is a term commonly used in reference to rechargeable batteries, but can also apply to 3D printers and other devices that contain heating elements. It happens when components responsible for regulating temperature fail, causing the element to get hotter and hotter until disaster strikes.
Bed adhesion problems can also be risky, since filament can stick to the nozzle and eventually burn or combust. Other causes include faulty mainboards and wiring issues, particularly damaged wires.
As unlikely as this is to happen, there is no shortage of documented cases of 3D printers causing fires, whether that’s concerned Reddit posts or verified news articles.
Smoke alarms are your first line of defense
Put them everywhere and maintain them
Hopefully you already have smoke alarms in your house. In many regions, not having smoke alarms installed falls foul of building regulations. Smoke alarms are proven to save lives by acting as early warning systems; make sure yours are working, have batteries inside them, and are replaced in accordance with the manufacturer’s instructions.
If your 3D printer is already in a room where you have smoke detectors (like a spare bedroom) then you’ve likely already got this base covered. If not, it’s time to invest since it could be the best money you ever spend on your printer.
Consider a product like the Docking Drawer Fire Guard Outlet ($228). Plug your 3D printer into the included outlet and mount the smoke and heat detector nearby. The 3D printer communicates with the outlet, cutting power to the device whenever danger is detected.
Of course, you can do this for much less money. Many smart speakers can detect smoke alarms and notify you accordingly. Apple’s HomePod can do this, then send a critical alert to Apple Home, which notifies all household members with an audible alert. Home Assistant users can build an ESP32-powered sound event detector that does the same, which you could use to cut power to specific plugs if you want.
Fire extinguishers could save your home (and your life)
Prepare for any eventualities
The main benefit of a smoke alarm is to notify you. Power outlets and smart plugs that can automatically turn off when smoke or heat is detected are all well and good, but they’re not to be counted on. By the time your 3D printer (or another appliance) has triggered the smoke alarm, it might be too late.
Having a fire extinguisher nearby can be the difference between having to replace your 3D printer and having to replace your house. For electrical fires, you’ll want to use a “Class C” fire extinguisher. These either use carbon dioxide (CO2) or a dry chemical mix, with the latter being the most common household fire extinguisher.
Put one near your 3D printer (and in other areas of your house where large appliances may cause fires—think dryers, stoves, and so on), and learn how to use it. Extinguishers need to be maintained or replaced on a regular basis, since they can lose pressure even if you never touch them.
There are some dedicated solutions for 3D printers, like the BlazeCut fire suppression system. These start at $170 and release fire-suppressing agent directly onto the source of the fire when the temperature reaches a critical point.
Should you leave your printer unattended?
Not everyone is convinced
The last thing you should ask yourself is whether or not you are comfortable leaving your 3D printer working while you’re not around. This could mean leaving the house or going to bed and leaving a print job running all night while you sleep. With smoke alarms and an extinguisher, you have a chance to prevent disaster—but only if you’re around.
There is no simple answer here; you’re going to need to look at your printing habits and printer model, then decide for yourself. Many people avoid leaving clothes dryers running and batteries charging when they’re not around for a similar reason.
Remember: any electrical appliance is a risk
I don’t want to single out 3D printers unnecessarily. There are documented instances of electrical fires being started by 3D printers, just as there are with any other electrical appliance. 3D printers can be dangerous, but so can your stove or bathtub.
Take care out there!