Part I: System Setup

Step 1: Serial Port Access

Arch uses the uucp group for serial devices — not dialout like Debian/Ubuntu.

# Add yourself to the uucp group
sudo usermod -aG uucp $USER

Activate the new group in your current shell without logging out:

newgrp uucp

newgrp spawns a new shell with the group active. Alternatively, log out and back in or reboot.

Verify:

groups | grep uucp

Step 2: udev Rule for the Printer

The Ender-3 V3 SE uses a CH340 USB-to-serial chip. The kernel module ch341 is built-in — no extra driver needed. But we want stable permissions and a predictable device symlink.

Create the rule file:

sudo tee /etc/udev/rules.d/99-3dprinter.rules > /dev/null << 'EOF'
# Creality Ender-3 V3 SE (CH340 USB-Serial)
SUBSYSTEM=="tty", ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="7523", \
  MODE="0666", GROUP="uucp", SYMLINK+="ender3v3se"
EOF

Reload rules and trigger:

sudo udevadm control --reload-rules && sudo udevadm trigger

Now plug in the printer via USB and verify:

ls -l /dev/ttyUSB* /dev/ender3v3se

Expected output:

crw-rw-rw- 1 root uucp 188, 0 May 29 10:00 /dev/ttyUSB0
lrwxrwxrwx 1 root root      7 May 29 10:00 /dev/ender3v3se -> ttyUSB0

The symlink /dev/ender3v3se means you always know which device is the printer, even if you plug in other serial devices.

Step 3: Install OrcaSlicer

Flatpak (recommended)

Flatpak bundles all dependencies, avoiding the library conflicts that cause segfaults with native packages on Arch.

# Install flatpak if you don't have it
sudo pacman -S flatpak

If this is your first time installing Flatpak, you must log out of your desktop session and log back in before continuing. Flatpak needs the session restart to initialize XDG_DATA_DIRS and the xdg-document-portal service. Without this, you will get bwrap: Permission denied errors. A full reboot also works, but a desktop re-login is sufficient.

# Install OrcaSlicer
flatpak install flathub com.orcaslicer.OrcaSlicer

# Grant serial port access for USB printing
flatpak override --user --device=all com.orcaslicer.OrcaSlicer

Launch:

flatpak run com.orcaslicer.OrcaSlicer

Create a shell alias for convenience:
echo 'alias orca="flatpak run com.orcaslicer.OrcaSlicer"' >> ~/.zshrc && source ~/.zshrc

Alternative: AUR Binary

As of 2026-05, both orca-slicer and orca-slicer-bin AUR packages segfault on some Arch systems due to library mismatches. Try the Flatpak first. If you want to attempt the native package anyway:

yay -S orca-slicer-bin
orca-slicer

If it segfaults, remove it and use the Flatpak:

yay -R orca-slicer-bin