[fkahhaleh]

Hi guys..
I have been trying to get a good PCB board done with no success at all. (I have yet to be able to use my DesktopCNC to mill/isolate any usable PCBs)

My setup is a BigFoot MyDIYCNC desktop CNC, (anti-backlash wing-nuts, halical couplers and autoleveller setup)
I have attached a few images to show what is happening.

Almost every board I tried, comes up with some copper not completely gone, and if I do go for a 2nd or 3rd pass adding
more depth to get rid of the copper in those areas, I usually end up making more damage to the "good" tracks.

Using a 45 degree V-bit, tried going slow and fast, not much difference.
Used WD-40 on the board; not much luck.

Any suggestions why the bit would eat in one direction/way enough copper and on the return back (opposite side) not so much?
is this an unlevel clad board? (or copper coating?)
I thought autoleveller would help get rid of it.

Thanks for you feedback

Fadi