Our team is getting a Prusa MK3 soon, and I need suggestions on safety options during long prints. Obviously we can’t be around full time to monitor long prints, and I know the MK3 is a pretty safe printer with all it’s safety features, but the day one thing goes wrong and sets off the smoke alarms or sprinklers is probably the day the school re-evaluates if they want to keep us around. Additionally, this would be living in a classroom with other classes going on during the day, so we really need for this to be protected from curious hands. Any suggestions? Is there a good enclosure we could buy?
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I have had a MK3 and the biggest issue is that is sometimes messes up half way through. I have never seen a fire or smoke. However, Prusa does have these instructions for an enclosure: https://www.prusaprinters.org/cheap-simple-3d-printer-enclosure/
Though, I don’t have a MK3, I did buy an acrylic enclosure for my Robo3D R1+ from PrintedSolid, they also make an enclosure for the MK3.
In general, you can apply the same safety practices to a 3D Printer as you would to a toaster oven. Basic stuff like “Don’t put it right next to a wall”, and “don’t keep flammable materials near it” are simple ways to avoid issues.
Also, it’s good practice to keep your printhead from getting too dirty; don’t leave the extruder heat on when it’s not actually printing anything, wipe any leftover plastic off of the tip occasionally between uses, etc.
In general, the flash-point of 3D printing filament is too high to cause any major concerns, so the biggest issue is just keeping other flammable material (paper and such) away from the printer. If you were buying a cheap Chinese printer, there might be reason to be concerned about the power supply or other electrical components (since cheap printers tend to not have the same QC checks), but you should be fine with a Prusa.
While the instructions on that page are pretty good, I would avoid the $15 Photo studio tent option. That screams “fire hazard” to me.
It should also be pretty easy to build a simple enclosure with some 1" angle brackets and any 1/8" polycarbonate you’ve got laying around. My previous team did this after we got our first 3D printer and it worked quite well.
If the printer doesn’t come with them built in, thermal cutoff fuses can help prevent overheating.
For an enclosure the cheapest option is definitely to make your own. Anything from an old terrarium to a pvc frame with a cut up robot bag attached to it will work.
Yeahhhhh… I know it should be fine and never have issues, but I don’t work for the school and really, really have to cover all my bases. I just discovered over-stove auto extinguishers, so I’ll probably throw something like that over it with some kind of enclosure build. I may try the terrarium thing, that hadn’t crossed my mind.
Just make sure if you go the over-stove auto extinguisher route that it’s smoke activated and not heat activated, as you will get quite a bit of heat coming off the printer during normal operation.
Right yeah, agreed, I saw a few that looked like they needed to get hit with an open flame to kick in. I’d probably go with something like that.
In my opinion, don’t worry too much about safety and a 3D-printer. I have been printing for 6 years and never once have I had an accident or even a close call.
If you are worried, a silicone sock around the nozzle and heater block could be a good idea. I never actually touched the outside of a silicon sock while printing, but that may make any burns someone gets from touching the heater block less sever. The Mk3’s fan shroud makes it really hard to burn yourself though, so I don’t know if that is even a concern. (Also the bed shouldn’t be hot enough to get burned unless you print exotic materials).
Remote monitoring is also nice. On my CNC router, I live stream to youtube with a Linux computer and a USB endoscope that has an LED built into it. This only lets me see where the machine is cutting (or laying down material in a printer’s case) but this is good enough for me. I also added a wireless kill switch. This way I can be sitting at my desk working on something while watching and listening to the CNC run at the same time. If anything goes wrong I just click a button on my computer and the machine turns off.
https://www.youtube.com/watch?v=4tpxgZUYGSI
If you are worried about fire safety, this video is a pretty good discussion of fire safety. It discusses CNC routers but most of what is talked about will also apply to a 3D-pinter.
I got a pulse which is based on the prusa design and I built an enclosure out of poster frames my daughter was going to discard after she graduated college. Those printers have quite a few safety features and will shut down if they detect a thermal runaway or something of that nature. Depending on the hotend you have you can run that anywhere up to (and above if you refit it wth a copper plated one) 300 C. Plus the bed will get somewhere close to 100C maybe 110 depending on ambient temperature. So there is a chance of burning your fingers. So I would keep it out of the reach of little children. If you build a real good (almost air tight) enclosure then build it in a way to keep the electronics outside of it and make sure any plastic parts inside the printer are made/prnted out of a material that can take the heat. Before I will build a real good enclosure to increase ambient temperature unside the printer I will replace the plactic parts that stay inside with ones that dont deform until a temperature way above 100 C
I have four printers in my classroom and after having the same safety concerns, I decided to install a $30 Nanny cam that had pan/tilt capabilities along side a $20 smart wifi powerstrip.
Now, via my phone, I can monitor the printers progress from home, and turn off each individual printer when it completes the print or messes up, therefore saving filament.
The Prusa line of printers is one of the most advanced printers available and should have almost all the software based failsafes out there. I have a cheap 3d printer at home (Tevo Tarantula) and a couple suggestions.
First, check the current path/connectors for the heat bed regularly. That is the highest current path in the printer and highest fire risk. Most of the cheap printers recommend putting in an external MOSFET to drive the heat bed to avoid the cheap traces on the motherboard.
Second, secure your printer down. I was printing a decent item (like in the 2-3 hour range), left the room, and my printer fell off my desk! I didn’t have a spool holder, so I left the spool on its side to pull up filament. I guess the filament got caught or something, the printer kept trying to pull filament, kept creeping closer to the filament roll and off it went. It ended up making a big spaghetti mess (it keeps printing no matter how it’s oriented) and melted a toolbox, and probably could have done more. There are a lot of designs out there for a “Lack Table” for 3d printers (basically just mount it to a $10 table from IKEA), you can stack a second table on top and enclose with plexiglass (also helps make ABS print easier as it likes heat).
There’s that word again. I run into a lot of issues with that word.
My MK3 has had the power supply fail twice, but when it goes it tends to just click for a minute very loudly and then shut down, no smoke, nothing.
To the “should” part. The prusa and its open source clones/similars have all the safety features. Problem is that it is open source and easy changeable and I know of some who turned certain safety features off cause they got “tired” of the warnings/shutdowns. And then there is the chance you do something by accident cause you might not know what you are doing. That means before you play with the firmware - make sure you really know what you are doing and fix the problem if you have one instead of disabling the safety checks. If you stay within those rules it should be no more dangerous than a copier or a kitchen stove. Simply put analogy. It has a smoke detector but if it keeps going of find the smoke and don’t remove the battery to turn off the annoyance.
Sadly, the school wifi just isn’t good enough for a streaming thing like that. I’ll probably make a cheap plexi enclosure with an extinguisher built in as my just in case.
I have a Mk 2 at work and we’ve abused it a fair bit. I’ve had 12 hour overnight prints fail and in the morning you have a big glob of plastic stuck around the head but I’ve never had any smoke nor fire. Some kind of case would probably be best though; for those students with more curiosity than is good for them (though I will admit a moderately preheated bed is a wonderful hand warmer on a cold morning right after I get in).
If you’re worried I’d give a second thought to a nanny-cam though. the vast majority of the time all you’ll be looking for is a failed print and for that you won’t need a 4k 60 fps feed or anything: if you can set the resolution and frame-rate I’d be comfortable with a 1080p slideshow at less than 0.25 fps. That would lessen the load on the network to near unnoticeable levels.
I’ve been using RepRap style 3D printers for longer than most, seeing as I helped with the early RepRaps…
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Sometimes filaments lap over on spools…you might physically pull in the spool.
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Often spools have dimensional irregularity of the diameters across the filaments…it can jam or break the filament.
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ABS prints can warp and interfere in the printer movements.
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Adhesion to the print surface can fail and in some cases it can jam the printer movements.
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RAMPS controllers usually current limit before smoking.
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Cheap power supplies can smoke.
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Belts can fail jamming the mechanics.
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Extruders can smoke and in some cases catch flame.
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Hotbeds…in some designs…can be electrical hazards.
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Wires and the filament can get caught in some designs.
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It’s not unusual for some filament to get stuck to the side of nozzles…possibly jamming things up.
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Prints can and do fail. Leaving the printer to waste more time is probably not a good idea.
Lucky #13: Never forget things around the printer can surprise you: pets, leaks, curious people, power outages, computer failures, flooding, tornados, earthquakes, someone crashing into your house with a vehicle (yes stuff like this has happened).
If I am not physically present during all printing I personally have a box I put my printers in (none of my printers are enclosed) with basically a CO2 cylinder to extinguish fires, a web camera and some other sensors. I also have the ability to turn off the power entirely remotely. These sensors/control features are all provided by an Arduino Mega with relay shield and ethernet shield. The web camera is an old D-Link someone gave me. Keep in mind that these WizNet shields offer no TLS/SSL so this is all behind a Linux firewall servicing it with OpenVPN.
Previously my box had a fan in it. I found sometimes the air flow it created was a problem. If I have to vent I made a flap. I suppose I could motorize that enclosure vent flap haven’t needed to, but maybe some day.
My enclosure is large enough the entire printer and feed spools are within it. The cables for communications/power exit through a notch at the bottom. So you could put this on after you started a print.
3D printers are basically CNC machines. One of our mentors had a HaaS literally burn out his shop running unattended one evening. Play safe and smart. It’s not terribly likely something catastrophic will happen, but if a: $10 Arduino Mega, $15 relay shield, and $15 ethernet shield with some sensors saves your several hundred dollar or more gear…do the math.
Many 3D printer packages that run a 3D printer from a PC offer remote access features. I set my stuff up so that I only depend on my Linux firewall PC: which has 3 Internet connections, UPS for it & the ethernet switch, and good hardware from HP/Intel. For some people the software may be a better fit. Be aware that I also have Arduinos on other CNC devices and for home automation so naturally this approach was easy for me.
I previously helped a student on ChiefDelphi write a very simple web server for the Arduino and if not the web graphical interface it can provide a REST interface. I just keep updating that work for new WizNet chips, Arduino packages and slight web browser changes (like favicon requests). If someone wants a better web server consider the NanoPi Neo2 with an UNO dock so you can leverage the Arduino shield ecosystem in the same way.
To the “should” part. The prusa and its open source clones/similars have all the safety features. Problem is that it is open source and easy changeable and I know of some who turned certain safety features off cause they got “tired” of the warnings/shutdowns. And then there is the chance you do something by accident cause you might not know what you are doing. That means before you play with the firmware - make sure you really know what you are doing and fix the problem if you have one instead of disabling the safety checks. If you stay within those rules it should be no more dangerous than a copier or a kitchen stove. Simply put analogy. It has a smoke detector but if it keeps going of find the smoke and don’t remove the battery to turn off the annoyance.
I shouldn’t have posted the “should” thing. It’s just a robotics related pet peeve of mine, but I wasn’t trying to cast doubt on the Prusa.
Prusa i3 MK3 has the thermal protections that are supposed to be there. Some other printers don’t. Here’s Thomas Sandlanderer testing some of them, including Prusa: https://www.youtube.com/watch?v=ckQ9UWlmdVA
It was surprising to learn that even the popular CR-10 doesn’t have thermal runaway protection turned on in its firmware. That sticks out since it’s an issue that causes fires with the infamous Anet A8 printer.
Both the kit in the YouTube description:
https://m.gearbest.com/3d-printers-3d-printer-kits/pp_664899.html?lkid=11104656
And the kits on eBay from Anet have never demonstrated to me they are exceptional fire hazards.
Being some are mostly part kits, latitude for poor assembly can not be accounted. Obviously assembly should involve inspection: and I know they don’t always send the exact same parts over time.
The stock Anet firmware though, there in is an issue:
In the video he’s not using a RAMPS PCB as a controller, the result is the Allegro stepper drivers are not there with their respective self-protection features. Some consider this RAMPS controller an upgrade, I am not one of that group, Anet printers are really cheap, RAMPS are cheap, no sense cutting too many corners.
And here’s how people beef them up:
I honestly have more than one Anet printer and none of my printers have ever burst into open flame.