OrcaSlicer/doc/calibration/cornering-calib.md

Cornering

Cornering is a critical aspect of 3D printing that affects print quality and accuracy. It's how the printer handles changes in direction during movement, particularly at corners and curves. Proper cornering settings can reduce artifacts such as ringing, ghosting, and overshooting, resulting in cleaner and more precise prints.

Types of Cornering Settings

Tip

Read more in Jerk XY and check Cornering Control Types

Calibration

This test will be set detect automatically your printer firmware type and will adapt to the specific calibration process.

• Klipper: square_corner_velocity
• Marlin 2:
  • Junction Deviation if Maximum Junction Deviation in Printer settings/Motion ability/Jerk limitations is bigger than 0.
  • Classic Jerk if Maximum Junction Deviation is set to 0.
• Marlin Legacy: Classic Jerk.
• RepRap: Maximum instantaneous speed changes

Note

This calibration example uses Junction Deviation as an example. The process is similar for Jerk calibration; just read the Jerk values instead of JD values.
JD values are between 0.0 and 0.3 (in mm) while Jerk values are usually between 1 and 20 or higher (in mm/s).

1. Pre-requisites:
   1. If using Marlin 2 firmware, Check if your printer has Junction Deviation enabled. Look for Junction deviation in the printer's advanced settings.
   2. In OrcaSlicer, set:
      1. Acceleration high enough to trigger ringing or the speed you want to check out (e.g., 2000 mm/s²).
      2. Speed high enough to trigger ringing (e.g., 100 mm/s).
   3. Use an opaque, high-gloss filament to make ringing more visible.
2. Open the Cornering test.
   
   1. In this first approximation, set a wide range of Start and End values.
      • If you don't see any loss of quality, increase the End value and retry.
      • If you do see a loss of quality, measure the maximum height when the corners start losing sharpness and read the Cornering/Jerk/JunctionDeviation value set at that point in OrcaSlicer.
        
        
   2. Print a new calibration tower with a maximum set near the point where corners start losing sharpness.
      RECOMMENDED: Use the Ringing Tower test model to more easily visualize the jerk limit.
   3. Print the second Cornering test with the new maximum value.
      
   4. Measure the maximum height when the corners start losing sharpness and read the Cornering/Jerk/JunctionDeviation value set at that point in OrcaSlicer.
      
      
3. Save the settings
   • Into your OrcaSlicer printer profile (RECOMMENDED):
     1. Go to Printer settings → Motion ability → Jerk limitation:
     2. Set your maximum Jerk X and Y or Junction Deviation values.
        
   • Directly into your printer firmware:

     • Restore your 3D Printer settings to avoid keeping high acceleration and jerk values used for the test.

     • Klipper:

       • Skeleton

       SET_VELOCITY_LIMIT SQUARE_CORNER_VELOCITY=#SquareCornerVelocity
       

       Example:

       SET_VELOCITY_LIMIT SQUARE_CORNER_VELOCITY=5.0
       

       Note: You can also set square_corner_velocity persistently in your printer.cfg (restart required).

     • Marlin 2 (Junction Deviation enabled):

       • Skeleton

       M205 J#JunctionDeviationValue
       M500
       

       Example:

       M205 J0.012
       M500
       

       • To make the change permanent in firmware, set in Configuration.h and recompile:

       #define JUNCTION_DEVIATION_MM 0.012  // (mm) Distance from real junction edge
       

       Also ensure classic jerk is disabled if using junction deviation:

       //#define CLASSIC_JERK
       

     • Marlin Classic Jerk / Marlin Legacy:

       • Skeleton — set the per-axis jerk limits using M205 (X/Y optional depending on firmware build):

       M205 X#JerkX Y#JerkY
       M500
       

       Example:

       M205 X10 Y10
       M500
       

     • RepRap (Duet / RepRapFirmware): IMPORTANT: Set in mm/min so convert from mm/s to mm/min multiply by 60.

       • Skeleton

       M566 X#max_instantaneous_change Y#max_instantaneous_change
       M500  ; if supported by your board
       

       Example (Duet-style):

       M566 X3000 Y3000
       

Note

RepRapFirmware exposes M566 to set allowable instantaneous speed changes; some boards may persist settings with M500 or via their web/config files.

Credits

• Junction Deviation Machine Limit @RF47
• Cornering Calibration @IanAlexis
• Fast tower model @RF47
• SCV-V2 model @chrisheib