I’m thinking calibration process issues here.
I’m using a top-mount kit like the one pictured. I just did a full calibration using v1.02. I checked that the motor spacing (3365.37mm) under load matched the motor spacing at rest. The rotation disk radius after the calibration (116.815mm) is the same as the previous time I did the calibration. This calibration gave 1905.2 on the first cut. This value for rotation radius seems odd, as David’s esitmate for the value was 133.35mm or 136.525mm. I’d like to see a diagram that shows just what is being measured here. At any rate, the calibration test passed, so the machine should be accurate.
As a test, I ran 20" up from the center position and made a mark, then 40" down and made another mark, then back to the center position. It returned to the center position precisely. The upper mark, though, was 19 15/64" above the center, and the lower mark was 19 47/64" down.
Moving 37.5" to the left and right to make the same pattern yielded similar though slightly different results. The bottom marks lined up across the sheet, the left and right center marks were 5/64 above the center mark, the left and right top marks were 19/64" above the center top mark. I pulled the sled down and vewrified thatn then center of rotation for the