XY Skew Calibration Test Part

prusaprinters

<p>Correct your printer's skew in the <strong>XY</strong> plane using this calibration part. <strong>XY</strong> skew causes parts printed flat to become stretched on one diagonal. Squares become parallelograms, circles become ellipses, etc.</p><p>Align the part with the diagonals of your print bed, then measure the lengths of the legs after printing. You can calculate the correction factor for use with a script such as <a href="https://github.com/MechanizedMedic/gskewer">gskewer</a> using this formula: <strong>xytan = 1 - sqrt(4b^2 / (a^2 + b^2) - 1)</strong>. In this formula, <strong>a</strong> is the size of the part on the <strong>+x/+y</strong> to <strong>-x/-y</strong> diagonal, and <strong>b</strong> is the size of the part on the <strong>+x/-y</strong> to <strong>-x/+y</strong> diagonal.</p><p>The nominal size of <strong>a</strong> and <strong>b</strong> is <strong>150 mm</strong>.</p><h3>Example</h3><p>Here are actual measurements from calibrating my own printer. Although I used mm, the formula will work with any units. This was using PLA.</p><p>Measured lengths of legs: <strong>a = 149.2 mm</strong>, <strong>b = 150.08 mm</strong></p><p><strong>xytan</strong> = 1 - sqrt(4 * 150.08 ^ 2 / (149.2 ^ 2 + 150.08 ^ 2) - 1) = <strong>-0.00586</strong></p><p>After applying the skew correction, the next part came out much closer: <strong>a = 149.62 mm, b = 149.60.&nbsp;</strong></p><p><br>&nbsp;</p>