X and Y axis off?

I in need of some help.

I have made a 100mm square square test cut to check the accuracy of of my mpcncs. It’s exporting correctly from my design program. I made a grid of the exact same size in Estlecam to verify the size in estlecam. Then use repetier to create gcode. However when I cut it its not perfectly square. More of a rectangle. It’s off by 2mm. Any ideas why this this is happening?

All toothed pullies are identical.

These things should all be included in your post. It makes it much faster to diagnose problems.

  1. Did you buy everything from here?
    a)If you didn’t or changed some things please don’t leave out any details.
    b)What firmware?

  2. Are you using end stops?
    a)If so please disconnect them.

  3. Are you using all my recommended parts?
    a) If not please list what parts you used.

  4. Include a picture so obvious errors might be spotted.

  5. If it is assembled how big is each axis?