Need help with Z cutting too deep (Solved)

ok. this is only my 2nd carve on the machine and trying to use these first projects to learn what i can so doing things myself verse purchasing things. this particular issue is carving out a dustboot and having issues with the Z axis cutting to deep in the adaptive clearing path.

in the fusion 360 simulation it looks perfect, and when i get it started on the cnc it also starts out well, but it just doesn’t seem to stop at the bottom lip and keeps cutting through the entire project.

i have probed x/y/z - xy seem to be perfect, but z just doesn’t seem to be accurate. i believe i am probing z correctly and is the first bit being used so there hasn’t been any bit changes yet.

can anyone help me narrow down what i am doing wrong?
i have also took calipers to the probe and adjusted in the settings to the same dims.

The goof up on the right was my fault with depth of cut and my clamping method (tape - no bueno and lessoned learned on cutting depth passes)
but what you don’t see on the edge is that the bit took another pass and cut off 2 sides all the way to the bottom before i stopped the cut.

Hey Joshua,

do you have the workpiece zero on the top or on the bottom of the workpiece?

Do you reprobe Z somewhen, after initial XYZ probing?

Zero at top.

And once zeroed xyz i havent stopped or zeroed again.

That’s why I’m so confused.

Hey Joshua,

And your workpiece has exactly the height that the 3D model has?

Yep. Just checked that this morning.

Im starting to wonder if i screwed up the z height on the masso when i adjusted to my probe.

Going to check that

Nope. Offsets all legit. Humm.

Hey Joshua,

you said you “believe” you probed Z correctly. How exactly did you probe Z?

Probe on corner get xy
Lift z over probe. Probe z.
Probe doesnt move.

From this it looks dead on.


Hey Joshua,

which touch probe are you using? I cannot see it in your images.

What kind of bit is that? Is this the bit you use for milling this?

Its the probe from onefinity. Purchased with journeyman.
Bit is 1/4 upcut 3in long.

Hey Joshua,

is there a special reason why you probe Z separately?

EDIT, ah i forgot. We’re on the Masso, not on the Onefinity.

I thought thats what you had to do on the masso?

Corner first. Then z
Different than the other controller.

Hey Joshua,

what are the values you have in the top probing settings?

ah i forgot. We’re on the Masso, not on the Onefinity.

I think you can see them in the last photo.

This is where i edited the offsets for my particular probe.

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Hey Joshua,

yes I see the dimensions of the probe height and width of the ridges.

Do you think we’ve eliminated the hardware and probing causes? If so, I can think of 1. your g-code program 2. Since you use an upcut bit, could it be possible that the workpiece is lifted?

By the way, is this HDPE?

No doubt its user error…just trying to figure where i went wrong. It must be code related somehow i think we have exahusted the hardware possibilities which is good. Narrows it down at least.

This is HDPE 1" thick. And although it did end up lifting off my work surface it was cutting well over 1/4in too deep prior to my holding method failing. Going to be screwing it down next time.

It is messing up with the adaptive clearing tool path and although looks great in simulation there must be something going on i am just not aware of.

Also this machine is a beast and love using it even if im on the learning curve.

Appreciate the help @Aiph5u

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Looking at your part vs the simulation it’s clear your z zero point is too low, the retracts where it travels between points are carving lines in the top of your workpiece, these should be well above the workpiece as you see in the simulation (lift Z, traverse X,Y). Did you alter any of the values on the heights tab in Fusion 360?

@WaywardWoodworker that’s what i was thinking as well… went back and checked and they looked as i would have expected, but now i am going through and specifying the bottom height of each path vs relying on the default “selected contours” maybe that will force it to stop at that height… i dont’ think that was/is the issue but worth a shot.

your assessment of the z height sounds like the correct issue… i just don’t know what i did TWICE to make it off.

zeroed at the top of workpiece
model height = workpiece height exactly
heights set in fusion 360 as shown above

zeroed shown in images above look correct…

going to run another test with 1" mdf and see what i can figure out

btw thanks to you two for helping me narrow it down. at least now its just one thing to figure out where i am screwing it up.

Hey Derek, hey Joshua,

as I don’t use Fusion360 I am not familiar with this simulation view, but you are right, the yellow lines that cross the circles are found as ridges in your workpiece (which cannot be intended). Sorry that I did not have a look at that earlier, I focused too mouch on probing and settings.