3D Printers catching fire? Is this true?.
Think of your beloved 3D Printer, it is printing flawlessly trough the night while you sleep.., and then suddenly.. Theres a nice cosy Fire!! why is this happening? how can we prevent it, and more important, how dangerous can it be?
Did this ever happen? Is there a real danger?
“Yes, mine did!”, Here we see some images from Claudio Luis Marques Sampaio, His printer’s thermistor came out of the heating block, which caused the fire. He also suffered from ABS inahalation, even using a gas mask!, so this is really dangerous!.
You can see more photos of the accident HERE
What are the most common errors that lead to a fire?
It always comes down to, who you bought it from, or how you assembled it. There are a few things that are likely to cause a fire hazard, as:
- Bad connection on the RAMPS board (power input pin)
- Bad power supply quality
- Not using a proper cable
- Poorly fixed thermistor
- Not using a cable holder
Lets talk about each one of them, Before we begin, notice that those are not isolated cases, they have been around since the first reprap designs.
Bad connection on the RAMPS board
This is more common then all the other, and it has even happened to me.
Remember those green connectors with screws? you NEED to screw it properly. do not go over this step!, also, on cheap ramps boards they will have a poor quality and are likely to fail, imagine that you need to pass a high current (20+ amps) trough a small wire, it will get pretty hot and burn the insulation, this is exactly what happens, there are a small contact area to a lot of current pass through when you don’t screw it properly, you can already imagine the outcome…
On the Sunhokey 3D Printer there is a similar problem, that you should check out here
Bad power supply quality
Ok, i was tempted to buy a 10$ 500w chinese PSU, but guess what? after a research of 3 minutes i found out that they only deliver about 140w RMS. What is RMS? it means the real power, how much can it handle for a long time. Why its so low? cheap components were used, for a low end computer it could work, since most computers dont even go above 150w rms with spikes of 300w. but if i used it for my high-end cpu, powering the water-cooling systems, GPU, CPU, etc, it would fail, since it really need those 500w, but we are not talking about computers, we are talking about 3D printers, so what is would mean for us? slow heating on the bed / noozle, motor fails, a lot of trouble, and, if we have a bad luck, the PSU will fail and possibly burn, causing fire.
Low quality cables
This is another common issue, cables can break over time (if they are not on chains or cable holder, their life will be even smaller).
You should always use flexible cables, fire resistant if possible, and always with cable chains or holders, this way, the service life is greatly improved,
DO NOT USE RIGID CABLES ON MOVING PLACES!, they will break and cause problems!,
Thermistor moving off the hotend
This is by far the biggest mistake that people make, the thermistor is not properly fixed at the metal body, and with time it just moves away from the heated block, which them make the software read a lower temperature, set the hot end mosfet to ON and powering it without control, the nozzle heats and is just a matter of time to the heat burn itself and then the ABS /PLA supports, this is extremely dangerous and there are a lot of registered cases where this happened! If your nozzle do not have a proper place to insert the thermistor just make a small hole for the thermistor and second one for a screw (to secure it in place)
Not using cable holders.
Cable chains are standard for most CNC’s and Robots on the market, it can avoid a lot of problems, like the cables going in wrong places, break and a lot of bad stuff, so why no should it be on our printers? we can even print one!, so, its cheaps, printable, and will improve you cables lifetime, so what are you waiting?
Now that you know what are the most common and dangerous mistakes, check if there is any issue with your printer, If you have any doubt or suggestion, please feel free to comment it below, or go to our forum ask for the experts!