I had this questioned answered with what I thought was an accurate solution in early August, but after attempting I still cannot get it right. So any additional insight would be appreciated.

I have an 11.25 wide board (a 2 x 12) and am trying to round off the corners exactly the same on each side.

Each time I attempt to round off the corners, the rounding cut starts at different points on each side - Ex on the left the cut comes starts at 3" from the top and it comes in of the left 3.125" from the top. I have attached a pic with my blue square highlighting the difference.

I have taken many runs at this using both the centre to material function, and zeroing in on the centre, as well as using the corner radius tool. But each time the cuts start at different on points the left and right side.

Any insight on this would be greatly appreciated. Thanks, Glenn