Z Height trouble shooting

Good day to everyone. I have a problem here that one of you can help me with.

the Z is all over the place.
the X and Y look great.
When doing pockets the z depth of the cut does not match what is set in toolpaths or in the save G-code. The depth is typically deeper than what is set and often varies.
After doing a number of tests I cannot discern a pattern or reason.

Measured thickness of material. Zeroed all to surface, bottom left.
one toolpath pocket is set for .325in deep and cut to .474in

Any experiential help and detective work will be greatly appreciated

camp clamp test.c2d (1.5 MB)
camp clamp test.nc (225.9 KB)

How are you setting your zeros? Are you referenced from the spoil board or the top of the work? Are you using a Bit Zero (V1 or V2)? How much deeper is the pocket? A common issue is to probe Z only when the Bit Zero (V1) is hanging over the edge instead of completely on the surface. This results in a cut about 3mm too deep. It always helps if you can post a file as well.

I posted the files to the original post - sorry forgot to do that.

the NC file looks OK. The depth of cut is aggressive the default tool profile is 0.060" (soft wood) your file is set for 0.200". Which Z axis do you have; Original belt Z, Z plus, or HDZ? If it is the belt driven Z, an aggressive depth of cut and an up-cut endmill could be overpowering the Z axis pulling it into the work. Does the cut sound OK? Does it cut OK with a shallower depth per pass?

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For your cut outs you are doc .20". The default is 0.040" So you are cutting quite deep per pass.

One suggestion for cutting out your clamps is that the long grain of the wood is going across your clamps. If you use your layout with a long board you might be cutting so the short grain is going across your clamps and that makes them weaker than if the long grain goes from the long end to long end. Always consider grain direction for clamps.

One more suggestion for your clamps is to always make your larger hole the same distance from the bottom. The reason for this is if you are using TEE nuts you have to be careful that you dont bottom out your bolts that clamp your cam clamps. If the bolts bottom out it can cause your spoilboard to rise up and give inconsistent cuts. In the future if you make more clamps you might have thicker wood or thinner and if you keep a consistent height of the bottom of the clamp to the bottom of the larger hole you can use the same bolts over. As you surface your spoil board you might have to get shorter bolts to replace the originals if they start bottoming out on the base board.

Ask me how I know this.