From 3D Musketeers channel: This SHOULDN’T Happen, Bambu - PrintFixFriday 224
A1s have been melting and after testing they managed to narrow down the cause of the issue - the termistor is at the limit.
Check out the video as they are explaining the issue in greater detail and having a call to action:
If you experience issues while your printer is under warranty - just have it repaired by Bambu.
Damn, this model has already been recalled for a known fire risk once before.
Why haven’t @BambuLab made a public announcement or worked (not just spoken) with the 3D Musketeers?
The last time this happened is wasn’t great, but, other than the huge delays in the offices, the communication was great, possibly the only time it was.
We need that honest communication before there is a solution, one house fire is one too many.
I literally just got around to putting in the replacement heatbed after the printer sitting dead for over a year from the last recall.
Then I see this. WTF. It sounds like it could be fixed via firmware? If not, is a hardware recall going to happen again?
He had a printer that was just 6 months old, so it must be pretty recent if they fixed the problem. Also would be good if they let people know about the problem instead of just quietly fixing it for new customers.
This was a recall announced a long while ago (Feb 2024) and I believe BL also sent out notice to customers of the A1 at that time offering two options to address this problem.
That said, Youtubers spending their days thinking of ways to increase viewership should not be a surprise 
That’s a different thing. It was a heatbed replacement before. This is under-specced electronics that can overheat and fail, possibly catch fire.
I got one of the early A1’s over two years ago and have used it extensively, even during the recall period. I have had absolutely no issues concerning the heat of the machine. Like with the issue with the cable, I’m inclined to think that the underlying problem tends to come from misuse of the machine. With the many thousands sold, should this not be a widespread problem? After all, the musketeer dude is claiming 100% possibility of failure.
Would be nice if someone at Bambu bothered reacting to this properly.
I bought an A1 on October 28th. I have an A1 mini and have not even taken the A1 out of the box. I hope it came with the new board. I have never had a problem with the mini.
I wonder if a DIY stopgap solution would be to desolder the part that gets too hot and simply move it further away by reconnecting it to the PCB with suitable gauge wire? Ideally maybe replace it also with an equivalent part that’s rated to a higher temperature from Digikey or Mouser.
I pose this as a question because 3D Muskateer identified two potential problems: the temperature spec on the part itself as well as its proximity to other heat sensitive parts because of the PCB board layout. Seems as though, in theory at least, moving it in this way might address both issues, provided there’s a suitable place to move it to. Just an idea. I don’t know enough to say whether or not it’s a good idea or a truly bad idea, possibly even worse than the current situation. Maybe someone with more knowledge could comment.
I was planning to buy an A1 but don’t currently own one, so it’s not yet something I could try even if I wanted to. I probably wouldn’t even contemplate it unless there were obvious signs of a problem, which sounds as though is more the exception than the rule anyway.
Alternately, just finding a way to pump some cool air to that location with a fan or something would be the least invasive and obviously might help mitigate against a temperature problem rising up too high or out of control. Or, if not that, then reducing ambient operating temperature.
Does Bambulab sell a replacement board in its store? You could maybe try that and just move on if it doesn’t exhibit the same problem, assuming it really is a problem in the first place. It sounds as though it affects some boards more than others, so a swap-out might gives you another roll-of-the-dice for a better outcome.
Really, we have an issue with… them… thre… temro… stor? Because ‘some guy’ on internet said so? Well, if on internet, must be true, right?
Anyone wants my A1? It’s still hot 
YouTube is not a source of endless wisdom or absolute truth. Learn to doubt.
And, kids, remember: don’t believe to strangers, Santa, and YT 
It isn’t a great design and they are probably using cheap Chinese parts which could have contamination problems, and/or they are damaging them in handling or soldering, and it appears they didn’t account for how hot these can get (easily 200C near the edge of the operating envelope), and it looks like they are mounted closer to the board than you usually do. I don’t know how they are being used cycle-wise, but they do have a finite life, lets say thousands of cycles and maybe the way they are using them exceeds that.
But I wouldn’t worry about it much on 110v.
I rolled my eyes so many times watching this video one of them got stuck and now I look like Marty Feldman.
In Grant’s defense the guy is extremely generous with his time and probably makes as much doing this as your typical McDonald’s manager. IIRC he is still driving a 78 ford pinto. He’s not getting rich at this.
Is there actually a fire risk? He’s not qualified to say. This has been happening for a year, minimum. Have there been any fires?
I don’t think belittling the situation is very smart. Just like everyone else, we are also just "some guy"s on internet.
The problem isn’t that we can’t doubt, the problem is: what if he was right and we ignored it?
A1 has been already recalled in 2024 so there is always a possiblity of a second recall.
That is my board he is showing there. I just turned it on one morning and when I checked it, it was dead, only the power light was on. I found the problem when I turned over the printer, then I could see the plastic was deformed. Got a new board after talking to support.
Got that printer in late february 2025 and it had around 1200 hours on it when it happend.
so there you are folks, mystery solved. The big question is, has anyone else had this problem. if so now is the time to speak up, and if this was a one off, it is time to put this post to bed. It is just scaring a whole lot of us A1 users.
Uh, what exactly was solved?
3D muskateers recommends putting the printer on a big concrete paver stone so that it won’t ignite anything combustable underneath it. Is that sufficient? Or could the whole printer become a torch if the print or the filament on it were to ignite? Is that even a concern?
If Bambu doesn’t want to make a statement, then, of course, it creates an unnecessary vacuum where every conceivable concern will rush in. They have all the data. They should just come out and say.
It’s really unlikely to be a thing at 120V. My back of the envelope calculations show a dissipation of 4W at 220V (quite warm for something that small) vs 1/3W at 120V (quite reasonable) and that is at maximum current (heater on full). So on 120V it’s much much less likely to ever get stressed enough to fail.
If you want to get an idea of how hot 4W is when concentrated into a small area, those old children’s filament night lite bulbs are about 4W, if you ever touched one as a kid.
Or if you know resistors, think about how big a 4W one needs to be (large) vs 1/3W (small).
MrDontCare said the picture in the video was from his printer, question being, was his the only printer effected, if so and no one else has come forward with the same problem, then I would surmise that the problem with the “fire risk due to thermistor overheating” posted by Johnny-Bit/3D Musketeers channel is a non issue. If it is an issue, why arn’t more 3Ders coming forward.
That’s a fair point. Melting plastic is one thing. Reaching an ignition point is another. As long as the circuitry is enclosed in fire rated materials, maybe that’s the final layer of protection for a worst case scenario, similar to how a junction box or wall outlet functions in a house?
Judging from the low uptake on this thread, I guess most people who own these things couldn’t care less. Go figure.