Klipper Sync for OrcaSlicer

An OrcaSlicer 2.5 plugin that checks your printer profile against the real Klipper printer.

It asks the printer's Moonraker what Klipper is actually configured for. Then it lists every setting in Orca that would stop a print, push the printer past printer.cfg, or make the time estimate wrong. Most of them can be fixed with one click.

Most Orca printer profiles are typed in by hand or copied from someone else's printer. Here is what goes wrong when they don't match Klipper:

Orca says	Klipper says	What happens
Build height 250 mm	Z travel ends at 212 mm	A tall part stops halfway with Move out of range.
Machine acceleration 20000	max_accel: 3500	Klipper takes the accelerations in the G-code as they are, so the printer runs faster than you tuned it.
Jerk 0	square_corner_velocity: 5	Orca's time estimate assumes the head stops at every corner, so it runs far too long.
Start G-code START_PRINT	Only PRINT_START exists	The macro is skipped as an unknown command. With the Klipper flavor, Orca adds no heating commands of its own, so the printer stays cold.

What it checks

Check	Compared with	Fix button
G-code flavor	must be Klipper	✔
Maximum speed X/Y	[printer] max_velocity	✔
Maximum acceleration X/Y/extruding/travel, and the process accelerations Orca will really send	[printer] max_accel	✔
Machine jerk X/Y (the square corner velocity Orca 2.5 uses for Klipper time estimates)	[printer] square_corner_velocity	✔
Z speed and acceleration	max_z_velocity, max_z_accel	✔
Printable area	the X/Y travel (position_min / position_max)	explains
Printable height	the Z travel	✔
Nozzle diameter	[extruder] nozzle_diameter	explains
Line width × layer height	[extruder] max_extrude_cross_section	explains
Nozzle temperatures	min_extrude_temp, max_temp (including a too-small margin)	explains
Bed temperature for the selected plate	[heater_bed] max_temp	explains
Firmware retraction (G10/G11)	[firmware_retraction], and retract_length set or set by a macro	explains
Exclude objects	[exclude_object]	✔ (turns it on in Orca)
Commands in the start, end, layer-change, pause and filament G-code	Klipper's command and macro list	explains
G-code thumbnails	formats Moonraker can read	✔
Process speeds above max_velocity	[printer] max_velocity	explains

"Fix" (Use Klipper's value) only changes the preset in OrcaSlicer. It is left unsaved, so you can review it, keep it by saving the preset, or undo it with Orca's revert arrow. Machine limits keep their silent-mode values; only the normal-mode values Klipper uses are changed. Settings without a fix button are explained instead, because the right fix may be in printer.cfg rather than in Orca.

Install

You need OrcaSlicer 2.5 or newer, and a Klipper printer with Moonraker (Mainsail, Fluidd and KlipperScreen setups all have it).

From OrcaCloud (easiest): open Klipper Sync on OrcaCloud and subscribe, while signed in to the same account as OrcaSlicer. You can also find it in OrcaSlicer under Plugins → Browse plugins by searching for Klipper Sync. OrcaCloud updates it for you.

By hand:

1. Download klipper_sync.py.
2. In OrcaSlicer, open Plugins from the main menu, click Install plugin and pick the file.
3. Tick Activate next to Klipper Sync.

Use

1. Select your Klipper printer in Orca. Its print host (the Wi-Fi icon next to the printer name) must point at the printer, for example 192.168.1.50 or printer.local:7125.
2. Press Space to open the Speed Dial, type Klipper Sync and press Enter. You can also run it from the Plugins window. A panel opens beside the 3D view.
3. The first time, OrcaSlicer asks whether Klipper Sync may connect to the printer's address. Choose Yes. The check carries on by itself, and Orca remembers the answer.
4. Read the list. Click Use Klipper's value on an item, or Fix all, then save the printer preset to keep the change.

The panel checks again when you pick another printer, process or filament, or save a preset.

Privacy and safety

• Klipper Sync only sends HTTP GET requests to the print host in your printer preset, or to the other address you typed for that printer: /server/info, /printer/info, /printer/objects/list, /printer/objects/query and /printer/gcode/help.
• It never sends G-code, never changes the printer, and never contacts anything else.
• If Moonraker needs an API key, Klipper Sync uses the one stored in the printer preset.

Troubleshooting

"Can't reach …" The computer can't see the printer. Check that the printer is on and that the print host address is right. Also check that the computer is on the same network as the printer: two routers can both hand out 192.168.1.x addresses without being connected to each other.

If the printer can only be reached another way from this computer, for example over Tailscale or a VPN, type that address in the box under the error and press Use. Klipper Sync remembers it for this printer and leaves the print host in the preset as it is. Click Use the preset's address again to go back.

"refused the request (HTTP 401)" Moonraker doesn't trust this computer. There are two fixes:

• add the computer's network to [authorization] trusted_clients in moonraker.conf;
• or create an API key in Moonraker and put it in the printer preset's print host settings.

"Klipper … isn't ready" Klipper is in an error or shutdown state. Fix it in Mainsail or Fluidd first, then press Check.

No permission prompt, and the connection is refused. Open Plugins → Klipper Sync → Permissions and allow the printer's address.

Development

The checks are plain Python and are tested without OrcaSlicer:

python -m unittest discover -s tests

build_report() takes a snapshot of Orca's settings and the data read from Moonraker, and returns the list the panel shows. Everything that touches OrcaSlicer lives in the KlipperSync class at the end of the file.

License

GPL-3.0. See LICENSE.