Uneven cut depth from left to right side of the macine

I am trying to carve a sign for my friends and I am not able to get even cut depth across the board. I checked for level and the machine is leveled. Not sure what the issue is. Below are some of the pics of the board for reference.

The fact that the term “level” is used can cause confusion fairly often, But the goal is not actually “level” but rather “Parallel Planes” The Spindle movement in X and Y direction needs to be parallel to the top of the workpiece.

It is recommended that the wasteboard be surfaced, which will help so long as the workpiece is parallel top to bottom . . . But a better practice is to surface the workpiece when possible. . And when that is not practical I sometimes use this shimming technique to get the top as parallel as possible in order to get perfect V bit engravings. . .

Here’s the official recommendation about surfacing the wasteboard:

And Here’s what I would recommend of using a smaller wasteboard atop the stock one that way it can be fully surfaced and you don’t loose the ability to carve onto larger boards. . .


I am having the same problem. I resurfaced my sacrificial board three times and still have the same problem like in the Sanchez Project above. Only way I can cut correctly is to add shims to the right side, not perfect, but it works. I didn’t always have this problem and not sure what is causing the issue now. Wider baords are the big problem. With a hand level, everything looks perfect. What am I missing?

well firstly, don’t use a bubble level. Use the cnc itself to verify parallel. Level is irrelevant in the CNC, it’s parallel that’s the spec to achieve…

Are you surfacing your workpieces on the CNC? Or Planing them first?

You may have to check your gantry and make sure it is tightened and not drooping across a large span. Checking for parallel planarity can be done in several ways including a machinist square across the span or at lease at both sides to ensure the same height in your case.

Are the retaining bolts on the waste board all tight. Just a thought