the machine is engraving offset,

the machine is engraving offset, i tried to engrave 2 concentric circles and the secong circle (the small one) is out of center ,moved to +y , anyone solved this problem?? enriqueturner123@gmail.com

Hi!! you need to do a reference pixel or square (using out bounds) for keep the reference, look the next article for more info: https://www.instructables.com/id/How-to-Cut-and-Engrave-Using-a-K40-Laser-Cutter/

My best guess your travel feedrate is beyond what the machine/steppers can support and it’s missing steps during moves. Try turning down your travel/move speed in the GCODE generation to something closer to your cutting speed and see if it cleans it up.

Is the offset the same when you run the same job multiple times? Loosing steps during engraving would possibly not allow to repeat on exactly same path. Is each circle a separate job or both are part of the same job? Do other jobs run correct?

Michael might be right, if your feedrate is set beyond machine limits when laser is not fired and you just move to another location, steps will be lost, but engraved shape will still look like a circle, as runtime feedrate is usually slower. Following this logic, is it possible that you overspeed on Y axis only?

I agree with @Djinn_per_se as this issue has been seen many times before. So make sure you have that reference pixel in each layer at the same spot so everything from layer to layer lines up appropriately. Alternately you could use another program like K40 Whisperer or Lightburn.