Depth of engraving inconsistencies question

Hello, I’m new here and have a Nomad 3. My main purpose of the machine is to replace handstamping brass plates to now engraving. The brass plates I’ve been working with are 2" in diameter and .033" thickness. On an 8x8 surface I can get 9 to fit so I made a jig out of wood and noticed some slight variations in the depth of the text. After reading on the forum, someone mentioned that they made their jib out of acrylic and the tape holds better and it seemed to be more consistent, so that’s what I did. The depth inconsistencies have gotten worse since doing this.

Things I have done to correct:

-Faced the wasteboard

-Reran pocket cut to go over jig again to make sure it didnt miss anything

-Took chisel and ran it along the bottom and around the edges since acrylic tends to meld and leave little globs everywhere.

Now the template/jig is tight and I did find that on one of them I didn’t press the brass plate in far enough which was the issue on that one but I made sure to tap them in with a screwdriver handle and all seem to be consistently the same depth.
When I run the program, they are all programmed the same depth, same font, etc. I zeroed the z axis just using one of the nine brass plates since they should all be the same depth. Some brass plates are engraved too deep while other brass plates are untouched on the same run. When I go back to zero the z axis onto the particular ones that went untouched, they come up at about -.002 or so different.
Why the inconsistencies? And what can I do different? My end goal, as with everyone else is to click the program and run the machine entirely through its program and not have to go back and do any special needs care on 4/9 brass plates.
Does the machine need calibrated? Try to resurface the pockets of the jig agan?

I appreciate all the help in advance and if any further information is needed from me please ask.
Also, I used the 102 Endmill to make the jig and I use a spetool .25mm radius (.5 diameter) ball nose end mill for my engraving. I use either advance v carve or v carve to run the program through. I’ve noticed that you need an engraver to use those functions so I’ve been somewhat tricking the nomad by selecting #501 engraver. I’ve tried “contour” for engraving but v carve and advance v carve are normally the ones that trace text without having all these crazy weird cuts where I don’t want them. Well, any advice, words or wisdom or ways to simplify would be amazing.
I also entertained getting the pro version of carbide create because it has a new engraving feature, is that worth it? Thanks again.

Semper Fi
Mike

The usual suspect on inconsistent depths for engraving is an uneven surface. You seem to have addressed that. Another culprit is the text font you use. Are you getting the same letters/numbers the wrong depth or is it a mixed bag. When Simple vcarve is used the vee bit goes as deep as needed to touch both sides of the lines. If the same letter is an inconsistent depth then maybe try another font. If it is a mixed bag try running a calibration using circles and squares of a particular size and then measure them in X and Y directions to make sure they are consistent. You make multiple squares and circles and see if each object is consistent. Sometimes the machine will not run smoothly over the entire surface and will cause inconsistent circles and squares. Some will be good and others the wrong size. If they are consistently not correct you can adjust the gbrl settings of how many MM per step. If they are inconsistent then look for mechanical issues. Have you oiled your ball screws recently. Dry surfaces can cause inconsistent results.

Can you also check whether your brass plate is flat and of a consistent thickness? Engraving with the CNC will highlight any anomalies here.

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