Welcome! Log In Create A New Profile


Smoke Signal - A Safety System for 3D Printers

Posted by amaurer 
Smoke Signal - A Safety System for 3D Printers
October 06, 2014 06:35PM
Hi guys - based on some scary posts I've seen around the web, I made a gadget to (hopefully) reduce 3d printer fires by shutting them off when smouldering wiring or components are detected. Printing unattended can be dangerous!

My Kickstarter is now live, I'd really appreciate your support!


You should never leave your printer unattended... but you do. This device will cut power to your printer when it senses smoke or fire.

What is Smoke Signal?

Smoke Signal is a "spot" smoke detector that perches over your 3d printer - at the slightest sign of smoke it will disconnect power to the printer within seconds.

How does it work?

You just plug your printer into Smoke Signal and position the sensor unit as close as you can to your printer's electronics or extruder.

Printer fires are usually caused by poor electrical connections that overheat and catch fire. By detecting the smoke emitted before an actual flame breaks out, Smoke Signal may be able to prevent a full fledged fire by removing the power source.

Why would I need this?

No 3d printer should be left printing unattended - a requirement that is at odds with the extreme duration of longer prints. Even the most conscientious operators, from time to time, leave their printer unsupervised.

Sadly, 3d printers do catch fire, sometimes with tragic results:




But I already have smoke detectors in my home...

Absolutely, and they're designed to save your life in the event of a fire while you're home. But a smoke alarm does nothing to prevent a fire in the first place, and cannot save your house if you're not at home.

Smoke Signal is intended to stop a fire before it occurs or spreads. A conventional smoke detector requires the entire room to fill with smoke before it will be trigger - the fire may well be out of control by this time.

Smoke Signal does not replace your home smoke detectors. And in some cases Smoke Signal may not be able to prevent a printer fire. BUT it does provide an additional layer of security and may well prevent a disaster.

Does this mean I can safely leave my printer unattended?

No. Smoke Signal may make it safer to leave a printer alone, but no safety system is foolproof.

Where should I place the sensor?

This depends on the design of your printer. Fires on 3d printers tend to start wherever there is a connection between two wires or elements - for example at the electronics connectors or the hot end resistor/heater.

Fans or airflow may make it more difficult to detect early or small wisps of smoke, so plan accordingly.

Putting the sensor in the top of a printer enclosure may produce the best results.

Can I use two Smoke Signals to monitor two parts of my printer at the same time?

Yes, you can.

However be aware that your locality may have codes or regulations pertaining to interconnected/"daisy chained" power strips or extension cords - Smoke Signal may fall into these categories.

How is Smoke Signal designed? What are the maximum ratings?

Smoke Signal is designed to safely run and switch printers (or other loads) up to 1000W (a typical printer uses perhaps 300W). The load relay is sealed and the power line is protected with a fuse (replaceable).

How long is the sensor cord?

6 feet. You can replace it with any standard ethernet cord should you desire a different length.

Is Smoke Signal certified or UL listed?

No - UL listing is too expensive. Smoke Signal's PCBs and electrical design comply with IPC-2221, an industry accepted standard for circuit board design. The smoke detector module uses an IC designed to comply with UL217 and UL268 standards. However no Smoke Signal-specific certification has been obtained.

Smoke Signal is supplied as a kit and should be treated as such.

What is the money going to be used for? Why Kickstarter?

$7,000 allows me to order PCBs and components for just over 100 units - this quantity lets me hit substantial price breaks at every stage of the process (parts, PCBs, and assembly).

Without support from the Kickstarter community, the loss of volume price breaks and the increased share of tooling/setup fees would make Smoke Signal impossible for me to produce.
Re: Smoke Signal - A Safety System for 3D Printers
October 13, 2014 09:04AM

Excellent idea, but do you have any plans for a version with a Euro or UK power connector (and to Euro spec 240v)

Re: Smoke Signal - A Safety System for 3D Printers
October 14, 2014 12:59AM
I would like to and plan to in the future, but unfortunately I can't do so during this Kickstarter.

As a stop-gap measure for international backers I'm offering a workaround of sorts (see project updates on KS):


International backers want international plugs. Really super badly.

Smoke Signal is compatible with most international voltages (90-250VAC, 47-63Hz) provided you can get things to plug in together. The plug-end of Smoke Signal can be swapped fairly easily, but the receptacle is hard.

As a partial solution, I offer the following:

Many printers and other household devices use a C14 receptacle for their power cord (like this: [www.commdevices.com]). If you wish to use Smoke Signal overseas and are willing cut off and replace Smoke Signal's wall plug on your own (with a hardware store replacement), I will send you a FREE US-style power cord for your printer that will plug into the US-style receptacle on Smoke Signal.

All you have to do is check if your printer uses a C14 style cord and send me a note with your address when the funding is successful that you'd like a free power cord.
Sorry, only registered users may post in this forum.

Click here to login