V Carving Thick Stock

I am trying to V Carve a logo into a block of Pine that is 4" thick.
I have prepped the file in V Carve Pro and I am using CNCj’s to send my g code.
I am using a Long-mill
Here is my issue.
When I zero my machine and do a test carve on a 3/4" piece of plywood, no issues.
When I zero the machine on the top of the 4" piece of Pine and run the Gcode , it’s like my zero migrates negatively into the surface by about 15mm.
I think this is because there is not enough clearance or retraction available and so the zero value defaults lower to accommodate the clearance and retraction???
Do I need to fix this in VCarve before I save the Gcode or can I do this in CNCj’s?
Any advice or insights are appreciated!

If the code is in absolute values and if you know the clearance height (mabye z=30), load the gcode in any text editor and do some strg+h. Replace each z30 command with something lower… z15 or so. But… no warranty that works.

The other (and more secure) way is to lower the clearance height in the CAM software and to rebuild the Gcode.

@isaaccull Welcome to the group, Isaac.

The Z0 is not defaulting to a lower value to accommodate the thickness of the wood. The gcode sender does not know how thick the wood is.

I suspect that you are physically hitting the top of Z travel when the cut starts, which throws off the Z0 that you set.

Make sure that you have mounted the router as high as you can in the bracket. After you set Z0, check to make sure that you have Z positive travel available before you run the job.

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Yes!
This is exactly what is happening!
I now remember having to move the router up in the bracket for something I did last year to correct for this problem.
I moved the router up in the bracket, ran the code and everything behaved as expected!
Thank you for that reminder!!!

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@isaaccull Glad to hear it, Isaac. Have fun.

As the original issue has been addressed, I’m closing this topic. If anyone else has a similar concern, feel free to start a new topic, which will ensure that it is addressed promptly.