3D printer nightmare fuel: Bambu X1C and P1P started printing while owners were asleep

When owners of Bambu’s extremely well-regarded 3D printers woke up on August 15th, some found their printer had gone rogue.

Some woke up to failed prints. Some found a second copy of a previous print. And at least a few found their Bambu X1C or P1P had started smacking itself apart — damaging components — while trying to print a second copy atop the object they’d actually asked for.

These printers started printing unattended, overnight, without any additional user input, according to a flood of user reports from the r/BambuLab subreddit, among other places.

What happened? In an official blog post, Bambu says it’s still investigating but suspects that a cloud outage is to blame. The company says its servers had two brief outages on Tuesday morning where the servers couldn’t confirm that the printers had actually printed — but instead of failing gracefully, they wound up sending the same print job again and again until it went through, Bambu’s staff believes.

“Simply explained, the print job sent to the printer before was trapped on the cloud and had a delayed start,” writes Bambu.

To say that’s concerning would be quite an understatement because fears aren’t limited to failed prints and damaged machines. 3D printers are one of the few remote-controlled devices in a house that can get hot enough to start a fire, and now, we’re learning that remote control system wasn’t fully thought through.

(Even if Bambu’s printers do have thermal runaway protection that might prevent a true fire from breaking out, Maker’s Muse suggested in January that system needed improvements, too.)

For what it’s worth, Bambu isn’t trying to hide behind some of the typical corporate speak we’ve seen around these sorts of incidents. Bambu writes that “we accept full responsibility”:

We wish to extend our sincerest apologies for this incident. We understand the frustration and inconvenience it may have caused, and we accept full responsibility. It is difficult to have a cloud service 100% reliable all the time, but we should at least have designed the system more carefully to avoid such embarrassing consequences.

Our R&D and Cloud Networking teams are working tirelessly to identify the root cause and ensure that this never happens again. We are planning to implement changes, such as additional verifications before a print is started, to prevent future issues.

When contacted by The Verge, Bambu would not go quite so far as to promise free repairs and replacements for all affected customers but says anyone who’s suffered any damage should reach out to Bambu support ASAP.

“For damage caused by this incident, we will offer the necessary solutions to our customers impacted by the Cloud Outage, in the form of part replacements or a printer replacement if the situation demands it,” spokesperson Taylor Liu tells me.

“Our team is working closely with our customers to provide the necessary assistance and make sure they are able to get back to printing in the shortest time possible.”

Liu says Bambu wants to make sure it’s finished investigating and documenting the issue before it updates customers again.

Issues like this also make us wonder about potential misuse and hacks, of course — if this printer can be remotely controlled by cloud servers to such a degree, what’s to stop Bambu employees and hackers from abusing that, including the live video feed from its cameras? Liu wouldn’t speak to that, simply pointing me to the company’s Wiki page on how it secures its printers. We’ve seen from experience with Anker that lots of well-meaning words about security don’t necessarily translate to practice, though.

To Bambu’s credit, the company has a robust LAN-only mode that you can turn on in the printer’s settings, which allows you to send jobs over home or Wi-Fi instead of across the internet. (Bambu even recently updated it with live video streaming over LAN, though you can currently only access that from the desktop slicer app, not your phone.) And you can always print from an SD card instead of sending files over the air, I suppose.

My own personal Bambu P1P is the best 3D printer I’ve used yet, and I’ve been working on a story about just how well it works for me. But I have my printer on a smart plug that can cut electricity after print jobs are done, and I may have to recommend that to others who are considering one.