Login

r/klippers

▲ 5 r/klippers

Looking for Pi 3 users with freezes or MCU disconnects on 64-bit MainsailOS / RPi OS (testers wanted)

Hi, I'm the maintainer of Mainsail and MainsailOS.

We've had reports of Raspberry Pi 3 SBCs freezing or losing the connection to the printer MCU when running a 64-bit image (MainsailOS or Raspberry Pi OS Lite 64-bit). One of them was posted here a few days ago: Klipper randomly losing communication with ATmega2560 on Raspberry Pi 3B+. I can reproduce it on my bench Pi 3 under load and I'm currently testing a possible fix. Before I change anything in MainsailOS, I need to confirm it on real printers.

Symptoms that might be related:

  • The Pi freezes completely (no SSH, no web UI) and sometimes reboots by itself
  • Lost communication with MCU in the middle of a print
  • USB devices (webcam or MCU) disconnecting and reconnecting
  • 32-bit worked fine, 64-bit doesn't

Who I'm looking for:

  • You have a Pi 3 (3B or 3B+) in your printer (maybe Zero2 could also have this issue)
  • You run, or have tried, a 64-bit image and have seen one of the symptoms above

What the test looks like:

  • Use a second SD card, so your current setup stays untouched
  • Flash MainsailOS 64-bit, copy your config and change a few lines via SSH (basic Linux knowledge helps)
  • Print as usual for a few days and send me some logs if something happens

I'll provide a step-by-step guide. If you're interested, comment with your Pi model (3B / 3B+), MCU board(s) and whether you use a USB webcam.

Even if you can't test, a short "I had this too" with your setup helps a lot to narrow it down. Thanks!

reddit.com
u/meteyou — 7 days ago
▲ 13 r/klippers

I Turned an Old Android Phone Into a Full Klipper Host

I’ve been working on AndroidKlipper, a project that runs Klipper, Moonraker and Mainsail directly on an Android device instead of using the phone as just a KlipperScreen/Mainsail client.

The printer MCUs connect directly to Android over USB host/OTG. AndroidKlipper bridges each MCU into a stable PTY, then runs the normal Klipper/Moonraker/Mainsail stack locally.

So far I’ve tested it on:
Retroid Pocket G2 — best-tested host; completed sustained real prints and long idle testing
Fire HD 8 — works as a host, but couldn’t charge while hosting USB with the hardware I tested
Moto G 2024 — clean install through Mainsail, normal Voron config upload, Klipper READY and successful homing

One of the biggest things I’ve learned is that USB-C + OTG + a powered hub does not necessarily mean an Android device can charge while remaining USB host. I’m documenting that per-device because it may actually matter more than CPU performance for long prints.
The goal isn’t to replace or hide normal Klipper. Your printer config stays yours, and I’m deliberately not weakening timing/safety limits to paper over Android USB problems.

Repo:
https://github.com/nozzlenaut/androidklipper

I’ve also been documenting the hardware testing on Unqualified Repairs:
https://www.youtube.com/@UnqualifiedRepairs

I’m particularly interested in people trying this on other Android hardware. Device model, USB setup, MCU type, charging-while-hosting behavior and long-print results would all be useful.

u/D__J — 7 days ago