Fire Risk cause by Lasers and printers and how to reduce the risk

I am new to this site and the use of a laser engraver, I see a lot of posts here and on facebook on lasers and 3d printers and the fire risk they present. I am making an enclosure for my Endurance laser diode machine non c02, This will enable the laser to be used in safety in the room where i am based and it will have to have a fume extraction system. one of the things i am thinking of installing is this to prevent a fire from spreading and also not to trash your laser or printer. I have put a project out to tender on upwork for a electronic firing mechanism that can be attached to a halon type extinguisher which will kill the power, turn off the extractor and fire the extinguisher all in under a second and save your printer or laser over the use of dry powder or Foam/Water, I came across this in my research today. This might save some of the work but not kill the extractor or power. The use of a Halon gas or similar will save your equipment when in most cases the fire is the workpiece and not the machine.

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That could save your house but not your laser. It is triggered by the melting of a fusible link. By the time it is triggered, the fire will be large enough to ruin the laser.

The absolute best thing you can do for safety is watch the machine when it’s running. At the very least, be present next to it and looking over every 30 seconds or so.

Some people think this is unrealistic, but electronics occasionally fail, so even though an auto extinguisher is a great backup, as Isaac says, it won’t prevent damage to the machine, and the false sense of security you get from having it there might lead you to take more risks than you otherwise would.


I totally agree but in europe 3d printers and lasers have caused house fires by being left unattended, i realise this extinguisher is not perfect this is why I have tendered on upwork for a series electronics experts to come up with a design that would trigger the extinguisher in a series of ways such as a heat or using an infra red cameras and so on, the circuit would then instantly disable power to the machine and the ventilation power and trigger the extinguisher in under a second, I am waiting for experts to come back to me with a tender to see what costs are involved and what methods would be best to trigger. The point is to try and save the machine and extinguish the fire at the same time. I agree this extinguisher is not perfect and your machine would probably be wrecked by the time it triggers but if the guys in upwork can come up with something that is better, faster and can be reused then it might be worth pursuing, in which case i will come to the community with the idea and ask for donations to help fund the design and creation of a system to save our systems and houses. Fire safety is an important factor to me having worked in the industry. You should never leave your printer or laser unattended at any time, if you have a camera rigged up to it you should have a monitor with you at all times to see what is happening, American houses are much more susceptible to fire damage than european houses simply because of the construction methods. I have used upwork before to create a system to power Nixie tubes in a certain fashion and at the same time the Nixies count up and down they send a pulse to RGB Leds to fire these, I use this design in my steampunk lamps I make and it makes for an interesting light show. The cost of the design work and list of components and instructions on soldering the lot together was 75 usd and i felt was a bargain for what it can do.

The best defense is good housekeeping of your machine. In this video Russ explains the dangers of the honeycomb and an alternative solution to using it. Also advises to clean up acrylic and other residuals after each use


If you want a very simple and safe system (no electronics or even mechanics) there has been a system used for years to protect engines (boats, planes).

They are simply two fire extinguishers connected to each other by a flexible hose that is passed over all areas that are likely to burn.

When a fire starts, it melts the pipe above the flame and automatically extinguishes the fire in the exact location.

But I don’t know if there are any systems that are small enough.
Check with the companies that maintain fire extinguishers.

However, the basic precaution is always to stay close to your machine to hear it and also to feel it.

Just a quickie…Halon is a banned product, which is a real shame as it was a brilliant fire extinguisher.

In a small room, its use can also kill the user due to suffocation, Co2 is safer and does not make much mess,

Yes, I know its been banned from non commercial use for quite some time, some server farms still use it but the extinguisher i showed was not Halon but one made with other safe no toxic gasses to replace the air one of the 3 ingredients of combustion. You could use Co2 as well but its not as effective the trick with all these the triggering system, you need a system that can trigger within a second or so to get the fire out before it trashes your machine and house, That is what i am working on with engineers in Upwork to develop a trigger, a electric cutout for power and ventilation and the ability for the system to be reused again at little cost. were looking at cameras, stereo thermal ones, infra red, heat detectors etc etc, once i have something tendered to me i will show the community to see if we can have it funded and made. I am sure the takeup would be large if we could make a fire prevention system in the 50 usd range. Thats what i am aiming at. it would also be used in the 3d printer market.

then why the need for an auto fire suppression??? I’ dont get it

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To make it double secret safe!

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Not too hard to take a basic smoke detector (have one planned for my enclosure) and make it fire off an extinguisher.
But even if you don’t use an extinguisher, a basic smoke detector can save you. Would let you know you had a fire or your ventilation system failed.

because people do leave their engravers alone and over here in europe some of us also have 3d printers which can run up printimes of 10 to 20 plus hours quite easily and its just no possible to stay at a printer with that length of time. camera monitoring helps but my feeling was of safety and to stop my laser or 3d printer being ruined by fire damage which is why i was looking at ways of triggering a device incredibly quickly, a smoke detector wont work the open diode lasers gives off smoke on every cut it makes and unless you have a ventilation system the smoke detector will just be on permanently. In europe there have been notable fires mainly caused by 3d printers failing, as i have one of each i was looking at it mainly for my 3d printer than my laser as i never leave that alone as the engraving is quick. But to develop a system for both i felt would be a good idea, the fact it could save your equipment and your house can only be a good thing. Most people dont even have smoke detectors in their properties where i live, in Spain yet in the UK they are a mandatory requirement for new houses and are connected into the electricity network so they all will trigger in the event of a fire, sadly here we do not have these rules. I rent a small apartment out here for tourists whichI have put a fire blanket, extinguisher, detectors and safety EXIT lights in it and is listed on airbnb and recently this year they even sent me a free combined carbon monoxide and smoke detector for it which was a brilliant marketing and safety idea. We can never assume a fire will not happen especially with 3d printers. That was my area of thinking but i thought it would be useful if i could have a system that could also protect my laser as well as my printer thats all, i am looking at two devices to save, one that you always stay with the other you do not. You only have to read the posts on here in the camera category and on the facebook page to see how many people leave their laser unattended and want the camera to run many more metres so it can come into the house from the garage where they have their laser installed so clearly a lot of people do leave their lasers unattended.

It is my opinion that these kind of machines need to be monitored all the time that they are working.

A spike in the Powerline can pass the psu and let the motion control go wild. About 10 years ago i had this happening … I was burning wood on a 100w co2 leetro based machine and the motion just stopped with the laser on at full power. If I wasn’t there… yeah… a fire would happen.

To make things stranger… I had a online ups with a tension stabilizer before that one… and yet the spike went through (the ups kept record of the surge)

If you want to work with these machines… monitoring is one of the prices to pay…

Anyway… this is just my two cents on subject… :slight_smile:

I have one of these over my Laser, one over the CNC and one in the basement utility space. I know it will not save the laser if a fire starts in it, but it might save the house. My laser is in the basement.

At 3 for $35 it seems like a reasonable extra safety measure. Of course the best thing is to never leave the laser alone while it is running.

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3 years ago I cut an acrylic job over a plywood nail bed and babysat it for 45 minutes. The following night I did the 2nd half of the job. With so many other things to do and the wife loading up the car for a trip the following morning, I left the laser to go help her. I have a laser/storage room behind my house in a 40x40 shop. I was only gone for about 10 minutes, probably more if the truth be known, I returned to a horrific surprise when I opened the door to my laser room in the shop. All I could see was black smoke and flames. The fire was so intense and so much smoke that I could not get to the fire extinguisher beside the laser. I grabbed another one from the shop, caught a deep breath, went inside and put it out. I had a 6 bulb florescent light fixture on the ceiling above the laser. The bulbs were all popped, melted, the wires to the fixture were hanging down toward the laser with the insulation burned off of them, the plastic 6" vent hose that ran up the wall behind the laser was gone (burnt up), the plexiglass window in the laser was gone, the ceiling and everything in the 12x25 room was covered in black soot. My guess, 2 more minutes I would have lost everything in my shop by the time the fire department would have arrived. Three weeks of clean up, lots of $$ and another laser, I was up and going again. I was lucky.


I agree with you, these, 3d printers and mini cnc’s all need strict monitoring for fire safety, at the moment my 3d printer in its own cabinet which is fireproof and i use an IP cameras to keep any eye on it at all time, I do not ever leave the house, the bed is always nearly at 80º c and that is hot.

The lasers are asking for trouble, that is next on my list and a friend of mine has his own cabinet with sand pit under the cutting area to catch the debris, basically we are burning wood normally so the risk on a 3 hour plus cut/burn is high, that and the fact we use an air assist means the risk is very high IMHO.

I am hoping to install some sort of Co2 dump in the event of flames but we will have to see, the cost is about 300 euros for this but the house is a hell of a lot more than that!

Then the cncs are all running hot on chinese electrics , and there have been cases of house fires from this kit, your photo above proves that.

At the moment if I leave the laser or cnc they are on IP cameras, my workshop is under my lounge as the house is concrete and brick and built into the side of a steep hill so partly subterranean, the workshop has fireproof doors and smoke detectors and i use a fume extractor but it does not mean i go to bed and leave it running… The laser has fume extraction directly above it using a stainless cooker hood with carbon filters.

I also have one of these football dry powder dumps but it would mean trashing the machine, small price to pay though… It is something that we all need to think about as our families and properties are at risk.

In mainland Europe the construction methods are normally, concrete and brick where as in the USA in parts a lot of wood and sheetrock (plasterboard, I think) is used… That is what we see here in Europe on American TV shows anyway. (I realise not everywhere)

It is always at the back of my mind… How far do we go and to what extent and what type of fire suppression system, co2 dumps, water sprinklers. Electricity cut off.

I can turn all my kit off automatically using a IFTTT instruction and a smoke alarm which is built into the circuit without me having to touch a thing. There is a water sprinkler above the machines that I can also operate If I need to using another IFTTT Instruction.

The kit is cheap enough and esty to buy.

There is always though the chance of a false trigger and then you lose the jobs on the laser and cnc, the 3d printer can stop and start. but if I was to turn the sprinklers on I would lose those as well. However not my house.

My water is is on a pressurised system and the workshop on its own pump and seperate circuit for water and power but shares the Cat 5. Is it overkill?

So the question is here “to what extent should be build into our properties/workshops Fire Suppression, Prevention”

Can it be built into the software? etc etc… or are we just worrying for the sake of it?

63º c is the trigger point on those heads, others are higher…

Don’t overthink the issue.

The fix is as simple as having a “professional” refillable CO2 extinguisher next to the machine, and always be beside it when it is running. Why refillable CO2? Because they’re really cheap to refill and leave no mess behind, so there’s no hesitation to use them if necessary on smaller fires before they damage something – and you can keep on working afterwards as if nothing happened.

I have a large CO2 tank I’m not using and was toying with the idea of having a system that would turn off the machine and fan, then flood the inside with CO2, but realistically it would never be used because if you’re standing next to the machine a fire will never go beyond needing to be blown out or smothered.

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I am in 100% agreement with this, i did look at having a complete electronic system which meant that i would not need to be there but in the end decided that the best course of action was never to leave the laser on its own or “unmonitored” , my lab/workshop is below my lounge and my house is typical block/beam/Concrete and brick construction unlike a lot of houses in the US or Canada. I live in europe and I am still paranoid about fire safety.

Therefore I have the same setup now a Co2 but on a dump system , the laser is enclosed in its own unit with ventilation so all i need to do is turn on the tap.

I also have smoke detectors which are networked so they set off alarms on my phone and with the use of IFTTT and Sonoff bridged units I can shut down everything as a result if necessary,

In dry tests its works flawlessly and the internet here is up 99.9% of the time so I need not worry about that not working and if it didnt I would not leave the room.

I also use a small cnc and a 3d printer and now with all that running the risk is unacceptable not to build in some simple monitoring equipment and preventative measures.

We all should be doing this. I own my house and I don’t want it to burn down.

When i am not in the room my ip camera is on my phone monitoring it and I have the ability to kill the power from the telephone and then go down and turn on the “dump”

I will not however ever leave the house or go to bed with the laser running. I have long since realised that this is way to dangerous to do, one pulse from my machine is enough to produce smoke and living in Spain where its hot and dry nearly all the time, living in a national park with a ban on BBQ’s etc you can understand the risks of fire more acutely especially after being evacuated twice from my house from forest fires in the last 20 years and not knowing whether I would come back to a ruin or house each time it tends to focus your attitude a little.

And yes concrete and brick houses do burn and they tend to self destruct having seen a couple of them after the forest fires here.

I never thought they would but the fire just sweeps through and as in Spain all the blocks in the building and bricks are hollow they heat up in the fire and the air chambers in the bricks and blocks cause mini explosions.

The bricks in the UK are solid and this does not happen but the floors are wood and they burn as a result of soft furnishings, in spain we tend not to have curtains or carpets often as we have shutters and tiled floors and use rugs but there are still enough items that will catch fire and cause untold havoc.

You can not take the risk of fire seriously enough Ladies and Gentlemen. It happens all the time and in europe we are seeing fires now caused by 3d printers being on for 20 hours printing almost continuously and one job after another or 4 of 5 printers lined up in a row printing and the beds on these printers are at 80 degrees nearly all the time and the hotend 190 and with cheap Chinese electrics the risk is too high IMHO.

I have all my kit PAT tested to ensure it complies with legislation, ( I have my own tester) if it fails I fix it. You would be surprised to see how much really does fail even well known brands over simple earths not being connected or a loose wire hair not being snipped off.

PAT testing kits are not expensive , a brand new one for residential properties costs around 250 usd and you can pick up decent second hand ones for less than a hundred.

It pays for itself in the knowledge that your kit is all safe and I offer tests for a small fee to test friends items and local residents kit. just enough to cover the initial cost of buying my machine and when its paid for the tests are then free. I am almost at that level now.

I dont stick great big labels on as there is no requirement for that unless you are in a commercial environment which i am not. just a simple little green and red dot , If its red I offer to take a look at fixing it for free. ( I’m retired) I have written off hairdryers, wands, lamps, tvs, dvd players, routers, apple TV !! IPTV boxes… etc etc, some i can fix others i don’t even go near.

So the moral here is please take fire safety seriously it does happen and I for one do not want to be a statistic.

Nearly all the control boards and kit we use are all produced from china and the power bricks in the market are crap mostly , they overheat and burn out, last week on the Sainsmart cnc forum there were two 5 amp power bricks burnt out as they were clearly fakes, just putting them on a metal tray would be enough to stop the risk of fire or burn damage. It really is that simple.!

Here are two photos, one is my neighbor’s pool being emptied ( we were then mandatory evacuated after this ) and the other is about 150 metres from my house! Luckily 3 helicopters came in at the right time and 2 fireplanes arrived and dumped retardant on the fire and road which is still stained red! A small price to pay for having your house!

Volunteer firefighters here called the ADF then come in and damp down, ladies and men who are paid nothing to fight the fires, in the housing valleys they are safe as the roads create natural fire breaks they told me but in the big fire photo they are not as there is no cover…

We opened up our house to them after the fire at 11:30 pm and all they wanted was water, some simple food and the ladies somewhere for a “p” in private… Incredible people.

I know this is all off topic but its fire we are talking about and yes this has nothing to do with an electronic fire it was Arson but in a wooded area and mountains where I live this is the consequence.


I use a laser commercially to cut paper/card and mylar film. If you have a strong air assist and extract the fumes through the bed then the air assist blows out any flames and the extraction fan draws any flames away from the combustible material. I also have a honeycomb bed and keep the area under the bed reasonably clean of debris.

My air assist is provided by a 3 Hp compressor which is only connected to the laser. My personal opinion is that the small blowers often used with the air assist are grossly inadequate.

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