[billbo911]

Originally Posted by protoserge

If you are running 2D Adaptive Clearing without a finishing contour pass, you would see this. Look under the "stock to leave". The default "stock to leave" is 0.020. So 0.020*2 sides = 0.040"

Would you mind sharing your file?

I was running 2D Pocket, not 2D Adaptive.
That said, I did look for "Stock to Leave" and sure enough, it was enabled and set to 0.02"!!! I think we found the culprit.

So now the question is, what is the best way to handle this?
Disable it?
Leave it enabled, but set to....?
How to finish it properly to size?

BTW, files attached.

Originally Posted by cad321

Is the 1/2in cutter you're using actually 1/2in? Do a quick check to make sure the cutter is worn or just undersize with a pair of calipers.

Nope, it measures .5000" (with our best calipers).

Originally Posted by thinker&planner

^^This.
That number, .040", is way to suspicious. I know that for Fusion360, the default "stock to leave" is the same .020". You can either make it leave no extra stock, or do a second "finishing" operation to clear out the remaining stock.

See above!