Skew Compensation
Corrects non-perpendicularity of the X/Y axes — when the frame isn't perfectly square, prints come out as parallelograms instead of rectangles.
Low priority
Printer-Specific
What It Is
Skew compensation corrects for X and Y axes that aren’t perfectly perpendicular. Even small angular errors (< 1°) produce visible dimensional inaccuracy — a square prints as a parallelogram.
What It Controls
- Angular accuracy (right angles in prints)
- Diagonal dimension accuracy
- Part fit for assemblies requiring perpendicularity
Why It Drifts
- Frame assembly wasn’t perfectly square
- Frame flex under motion forces
- Crash or impact to the frame
- Rarely drifts once set on a rigid frame
How to Calibrate (Manual)
- Print a large square (or use Klipper’s skew calibration object)
- Measure diagonals — if they differ, axes are skewed
- Calculate skew angle from diagonal difference
- Apply correction in firmware (Klipper:
SET_SKEW, Marlin:M852)
How the Auto-Tuner Calibrates It
- Probe grid at known coordinates — probe XY positions and compare to expected geometry
- Calculate skew from measured vs. expected positions
- Low priority: only needed once unless frame is disturbed
Related Anomalies
- Backlash Artifacts — can be confused with skew on diagonal features