For current owners who want to avoid Bambu's servers entirely, consider LAN mode with OrcaSlicer and this open source reverse engineered networking plugin: https://github.com/ClusterM/open-bamboo-networking

I have verified that my P2S in LAN mode never attempts to make external connections at all (blocked it anyway, of course) and OrcaSlicer + this plugin never attempts to connect to any of Bambu's servers.

My P2S is easily the best printer I've ever had, they really do make incredible machines, it's a shame they have created this ridiculous situation just to (as far as I can tell) collect telemetry.

I know I'm worried when they're going to start mandating client-side scanning of 3D prints.

https://www.eff.org/deeplinks/2026/06/we-can-still-stop-cali...

I have several, and they're all running in DevMode/LAN Mode. I drive them using this project:

https://bambuddy.cool/

This still sends query to bambulab if they don’t use modified networking plugin, unfortunately.

LAN mode works well with home assistant and some HACS Bambu integration. Takes some setup but then you get real time camera feed and all the nice sensors for temp, humidity, including any AMS you have. I connected mine to Bambu server for the app just to see what it does, and my home assistant setup still works over LAN. Great printers and for now offline modes work well.

Probably this one: https://github.com/greghesp/ha-bambulab

It's excellent for monitoring and setting up automations around printer events, I use it all the time too.

2nd this, I have my X1C blocked on any inet access, LAN only, it’s a very nice piece of hardware with questionable software :/

I run this on the home server w/ caddy-tailscale, and I can slice/print from anywhere with a nice easily rememberable domain name. I run a P1S in LAN mode and have it firewalled from actual internet access.

https://github.com/linuxserver/docker-orcaslicer

The Bambu Labs mobile app doesn't work with LAN mode. I found this app for Android, "LanBu" which does a decent enough job. It's still in beta and wants to display ads. So far my PiHole has blocked all its ads so it's tolerable. I wouldn't mind paying for it, if it's a one-time free and it allowed access from outside my LAN.

Is it possible to back out the firmware updates and setup that came along with this change to get self sufficient, or is that not necessary? I recall hearing that a firmware update made the printer (P1S in my case) phone home even potentially when in LAN mode. This is an area where I just kind of gave up and let it happen, though I kind of regret it now.

This part gives me hope, but I have not been able to find the certificate:

Option B: cloud mode without Developer Mode

Starting with v2.0.0 the plugin can also drive a cloud-paired printer with verification left ON — no Developer Mode. This keeps the cloud features (cloud print dispatch, print history, MakerWorld) but is meant for advanced users, because it requires private slicer credentials that this project does not distribute.

Two things are needed:

1. Bambu's slicer credentials, which you provide yourself. Put slicer_cert.pem, slicer_key.pem and slicer_crl.pem in the plugin's config directory (or point at them with slicer_cert_pem / slicer_key_pem / slicer_crl_pem in obn.conf). The plugin uses the key to sign MQTT print commands and to install its app certificate on the printer. These are private credentials. This project does not ship them and gives no instructions on obtaining them — you have to find or extract them yourself, and you alone are responsible for ensuring your use complies with the applicable terms and law.

2. Two settings in obn.conf. Set block_cloud = 0 (the default 1 blocks cloud printing outright) and client_name = BambuStudio (the honest default client name is rejected by the cloud print API with HTTP 403).

With that in place you get signed MQTT commands, on-printer app-certificate install, cloud print dispatch, print history and MakerWorld — without touching Developer Mode.

What the default cloud_print = cloud_only actually uploads. Even in this mode the model itself normally stays on your network: for a print with a cloud record the plugin sends the .3mf straight to the printer over LAN FTPS, and only the record goes to Bambu — a project entry, a task entry (mode=lan_file) and a small config .3mf that print history uses for its thumbnails. That record is exactly what buys you the cloud extras: print history in Studio and Handy, and the ability to rate models on MakerWorld. The full model is uploaded to Bambu's servers only when Studio dispatches a pure cloud print (start_print), e.g. for a printer that is not reachable on your LAN.

You can limit even that: set cloud_print = try_lan_first or lan_only to print over the LAN without writing a cloud record at all, and cloud_hide_history = 1 to hide the cloud print history in Studio.

If you run neither Developer Mode nor valid credentials, the printer rejects every print / project_file command and shows on its screen:

MQTT Command verification failed err_code: 84033543

I have never had any interest in using Bambu's cloud. It works in LAN mode with none of this rigamarole.

If you want to feed all your print activity to Bambu's servers anyway, why bother using an open source plugin in the first place?

Is it faster to send prints than using the cloud Bambu service?

I only sent one test print through Bambu so I can't make a comparison, but it's <10s from clicking print to the printer starting its warmup dance.

Speed is not why I set my printer up this way though. I live in a state that may ban 3D printers unless they include invasive surveillance, so I wanted to get a high end pre-ban printer in case that becomes law.

Oh shit, I didn’t realize that had been cracked. Nice, I’m gonna switch ASAP.

I bought a P2S, and then literally a few days later, the X2D came out. Thanks Microcenter, and your excellent customer service and return policy. The X2D is everything the P2S is, but with another nozzle.