Y Axis problem on K50 Chinese laser cutter

Hi All,

so i have a few of these machines and never really had any problems.

I recently got another 3 but 2 of them are having issues with the Y axis. All mirrors aligned and the machine cuts no problem at all. But when it comes to engraving it does not come out well. So it looked like the image was being stretched on the Y axis. With this in mind, i cut a simple square 170 x 170mm.
The X axis measures 170mm as expected but the Y axis measures 180 which suggests its stepping to far and ultimately why i can cut but not engrave.

Im using RD Works and I'm sure this is a simple setting that i have missed so i would appreciate any assistance. I have attached a picture of the messurements.

So this is a vector cut where the sides of the box are parallel to the X & Y axis. Each axis has a motor that has a pulses per unit in the controller. The machine has no feedback so it relies on calibration. If the calibration is off the square turns into a rectangle, circles are oval and so on. You calibrate this value by moving each axis as far as it goes and make sure the distance on the controller matches the actual distance moved by changing this setting, for X&Y and Z if you have it. I just use try and retry until it matches


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Thanks for your answer, yes thats exactly the problem, how do i make these adjustments on the controller?