I have engraved multiple rulers (10mm spacing) on a blank plate. First i engraved with x axis (from right to left and then vice versa) and the the same for y axis, overall 4 rulers. The result is the same as it was on my 5 parts with the error. X axis has 0.5mm error, y axis is ok. Engraving from left to right and vice versa doesnt show any error when comparing those two cuts. So i guess no mechanical error.

On the pics bellow it shows where the error appears. It is in the middle area, approx 0.5mm error. I circled where the camera shows correctly because of its lens.

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On following pics i fixed the ruler in the center of the engraved ruler and it shows the same error as on the part:

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This must be something with the servos. Is this fixable with servo tuning considering i have no clue how to fine tune the servos?