When I try to burn a simple rectangle, it comes a bit skewed. The sides are not perpendicular to each other. The size of the rectangle is 205mm wide by 305mm hight. I have tightened the belts on both axis and I dont notice any skipping of the belts. The Laser is Longer RAY5 and is fairly new. Has anyone faced this issue? What can be done to resolve? [20251127_115552]

Are your rails square to each other?

Can you round the corners of the rectangle and show what that output looks like?

Your gantry is most probably not perpendicular to the side rails. Measure distance left and right between gantry and front of the frame. If not perfectly equal, loosen a setscrew in the pulley opposite motor-side so that you bring the gantry in a perpendicular position and lock the set screw. Do a check with a 100mm square. Measure the diagonals with a calliper. They should be equal within 0,1 to max 0,2mm. The square that you cut out should fit in any direction when you did it correctly.

There was a 2 mm difference between the front of the frame and gantry comparing left and right!!! … Took a while to fix this. But this seems to have fixed the issue. Thanks!!

Here’s a nice way to test the squarenes: [image]Gantry not square Set up the largest square / rectangle you can do in your machine, and put a dashed line down the middle. I used old wrapping paper. Cut it and then fold it on the dashed line. If the corners come out even, congratulations, your X is perpendicular to your Y. If they don’t, the mis-match is how far out of square you are. You adjust one end of your Y axis drive by that amount, and you are now square. [image]

One axis not going perpendicular to other

LightBurn Hardware Compatibility GRBL

Aaron.F (Aaron) November 28, 2025, 11:49am 7

Here’s a nice way to test the squarenes: