Bambu Printer Fire Hazard Issues

[Alan B]

Apparently some issues in several printer models:

https://youtu.be/hiBRVFe1TyQ

[Ed Street]

This is an issue from several years ago.  They, Bambu, even had a recall and part replacement over it.  The problem is even deeper, going back a good 10+ years with bed slingers.  The unsupported cable is causing electrical arc, sparking, and catching fire.  There are even several videos out there showing printers sparking and catching fire.

[Alan B]

This is NOT the old umbilical cable problem, clearly Ed didn't review the video at all and just made assumptions. This is a different issue having to do with a very hot surge limiting thermistor that is adjacent to components not rated for the thermal environment being produced by this component. Bambu is aware of this problem and has chosen to not deal with it for awhile now (apparently) and it is becoming more public as more cases of it have become problematic and more printers have needed repair. This board is apparently used in several printers, not just the A1. He mentions they have collected nearly 100 failed pc boards from customer machines. To an engineer this appears to be a problem in design and pc board layout failing to provide cooling clearances and failing to properly size the thermistor for the power levels it is being used at, as well as not allowing appropriate safety margins, or perhaps choosing a different surge limiting solution that would not simply waste so much power as component heating.

--
You received this message because you are subscribed to the Google Groups "3D Printing Tips and Tricks" group.
To unsubscribe from this group and stop receiving emails from it, send an email to 3d-printing-tips--...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/913ffbb2-d379-4983-824b-828c1c7cce0bn%40googlegroups.com.

[Bryan Eckert]

I’ve been following this issue on Reddit for a bit, Bambu actually has changed the board design, per their wiki and photos that have been submitted by users showing that particular component removed. AFAIK, this is on European models running at 230V. 

The issue I have with 3DMuskteers is he does a lot of sensational stuff without really knowing the subject. For instance, he points out at the 2:00 mark in the video a component “melted”. Yeah, no kidding - that part is a time delay fuse. You can clearly read the rating. So it seems there was a component failure and the fuse did its job. When that is pointed out to him in the video comments he feigns ignorance. Not unlike when I noticed irregularities in his video on the firmware when he poked around after installing X1Plus. It was clear he didn’t understand Linux.

Bambu’s issue is one of popularity. The A1 and P1S (uses the same board) have sold tons of units, and they have to source from multiple vendors. The board design is likely fine, but the particular thermistor probably had a bad batch. We’ve seen this time and time again from all kinds of manufacturers, like Apple having cap issues in their iMacs, Asus having issues with motherboards, etc.

Thing is, this is a pretty standard power supply design, and if other manufacturers got the same batch then it won’t just be Bambu. Corsair had the same exact issue in their PC power supplies a few years back. 

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/CAHoVSn%2BK0u8zo-DRU51rsBg%2Bjb9ezc67zNYorgZpEJQJ203KjA%40mail.gmail.com.

[markni...@gmail.com]

Last year the Qidi plus4 had a potential fire issue that got a lot of attention.

To me all of these issues are caused by Chinese manufacturers using under specified parts in their designs, usually followed them offering a fix using marginally specified parts.

This is a video of a proper fix for the Qidi plus4: https://www.youtube.com/watch?v=kYKGGycYN2w

None of these machine hazards would ever leave the factory of say, Stratasys.

Now I realized that Statasys makes commercial machines costing many times more.

I think the solution for us, is to wait for a clever user to come up with a proper solution, like the plus4 video above, then copy it.

[Ed Street]

If you've seen the remark lately, the nvidia ceo said in China they can build a hospital over the weekend, whereas here in the state it will take 2-3 years.  The time difference is evident when you look at requirements, standards, and safety levels.  In the US, there are high safety standards for materials, design, and construction.  Also, in China, you have city or regional zones, and oftentimes they push to move it faster than usual. More often than not, quality, safety, ty, and value standards are dismissed, pushed aside, and forgotten.   So that hospital that is built overnight may collapse onto patients next week, or the floor may fall in, or the patients may die from heavy metals or other toxic materials used.

Also, I did watch part of the video and stopped when he mentioned A1, but it looks like there are other fire issues with them.  They have been dubbed the Bambu Death Traps for a reason :)

[Bryan Eckert]

Having had machines owned by Stratasys subsidiaries, I can tell you in no uncertain terms that yes, they have released garbage. We have machines sitting dead due to extruders refusing to work.

Also, looking a bit more at the components (which are not in the new board version) seems this issue is exacerbated by power standards in the EU. The 230V bed pulls 1000W when heating (US 120v is 350w) Except some areas operate at 240V, and can hit near 250V (UK particularly) which is where the issue lies. With 240V and 45 ohm, plus another bit for the hotend and motors and you’re about 5.5 amps and out of headroom. If power has upped to near 250V it will definitely happen. 

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/9073ab3e-00af-4a0e-8faa-fda64bf1fcbbn%40googlegroups.com.

[LukeH]

The issues with the Qidi Plus 4 weren’t a “substandard part” issue. The issue was that units destined for countries with 110V to 120V power supply were fitted with SSRs for 220V countries. Since at 110V you draw twice the current for the same power, the SSRs were overheating.

, 

Replacement parts were only required in some countries, since most of the world uses 220V to 240V power supplies (87% of the world’s population uses 220V to 240V appliances).

[markni...@gmail.com]

Clogged extruders are the bane of all FDM printers.

There are 25 year old videos on Youtube showing how to unclog Stratasys SST768 printers.

If one works in a Stratasys shop, and doesn't quickly learn to unclog an extruder, They don't last long.

What percent of Qidi printers are sold in the US? I realize the civilized world uses 220-240 volt service.

Given the ratio of printers sold in the US compared to the entire rest of the world, I would have thought it prudent to check if their SSR work at 120V.

[Luke Hartfiel]

I would suggest that 3D printer use in the US isn’t any larger, as a percentage of the population, as Europe (which has double to population), and is probably lower than in Asia. It would probably represent a single digit percentage of 3D printer users worldwide (given the US is like 4% of the total world population).

Should Qidi have tested their printers in every market they sell them? Absolutely. No question. My point was that the part used wasn’t sub-standard or faulty - it was just completely the wrong part.

On 28 Dec 2025, at 9:31 am, markni...@gmail.com <markni...@gmail.com> wrote:

Clogged extruders are the bane of all FDM printers.

You received this message because you are subscribed to a topic in the Google Groups "3D Printing Tips and Tricks" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/3d-printing-tips--tricks/Qo0YZRptADo/unsubscribe.
To unsubscribe from this group and all its topics, send an email to 3d-printing-tips--...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/a6b32e76-a980-4df2-9666-29036f7c019cn%40googlegroups.com.

[Bryan Eckert]

The smart extruder was next level crappiness, which caused a class action suit over which Stratasys lost nearly a billion dollars in a single quarter. 

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/a6b32e76-a980-4df2-9666-29036f7c019cn%40googlegroups.com.

[markni...@gmail.com]

Yup, all the result of the Makerbot debacle.

The smart extruders were on legacy Makerbot branded machines, not Stratasys.

They paid way too much when they bought that crap from Bre Pettis.

[markni...@gmail.com]

So I Googled "What percentage of 3d printer sales worldwide are in the USA?".

Google return: " North America dominates the global 3D printers market with the highest revenue share of around 32.14% in 2024".

[Ed Street]

That's what I get to, reasonable-ish.