I want my final material thickness to be 5/8". I set my material thickness in CC and zero’d my machine to the top of the material in CM. I set my Max Depth to t+.625 (hoping for a 5/8" finished material thickness). But the machine is milling deeper than that. What am I doint wrong?
Maybe I shold be setting Stock Thickness/Zero Height to “bottom” and not “top”?
If you want to zero off the spoil board (stock bottom) then you need to zero there, not the “top of material”.
In the first pic your zero height is set to bottom. Change that to top if you are zeroing on the top as you described
sorry, yes. I screenshot it AFTER I changed it to bottom. I was set at top w/ Max Depth “t-.625”
After milling my meterial is NOT .625"! it is closer to 1/2"
@Redlander You beat me to it 
So I’m doint it right then?
Set Zero Height to: Top
Set Max Depth (D) to: t-.625
Should it not be t+.625? Not thinking well here today…- would put you below t???
edit no that doesnt make sense 
No, the simulation takes like 111 mins to run at t+.
Strangely… I’m actually milling Mahogany… 
I normally zero off the top of material. That sounds right but I don’t normally use this method either. You have to make sure the actual thickness is dead on and need to measure thickness in several place. Even if you split the difference from .5” to .0625 is only 0.0625” which is 1/16”. The material might be cupped or warped a little and this could be your result.
Well, perhaps I was clairvoyant for once in my life?
It’s actually a running joke between Jeff and myself about the mahogany, Which I’ve really appreciated him being a good sport about.
I know it’s the easy way to use t … but why not zero off the top and set your max depth to what ever the difference is between material thickness and 5/8"?
Thanks guys. I really think by formula and settings are right.
@Jeffish - that is probibly the best idea and what i’d do most of the time. But I have a bunch of boards that I am trying to flatten to the same thickness - without haveing to math…
Im also using dbl-sided tape,which is adding about .004-ish to my thickness when fastened to the spoilboard.
Are you flattening both sides? If so, what Jeff recommends works fine
well, the process is to mill one side flat, then flip to mill side B to the final thickness
OR - I could just buy a diecent Planer…
If it were me, I would zero off the top then. It seems the main reason to zero off the spoil board is to prevent cutting into the spoil board. If just flattening you don’t have that worry. Everyone has their own preferred process however and neither is incorrect.
I’ve never discouraged someone from buying more wood working tools!!
And I’m never discouraged to buy more tools…
Well, think I’m just gonna have to go the math way… My teached DID tell me that I would need calculus one day… 
Thanks @Redlander & @Jeffish
Have you measured (and set) the thickness accurately?
