i have been cutting a 1x2 inch mortise.
at  1 inch per min.  but i am not getting a uniform cut.
just wonder what adjustment i can make to correct this.
thanks paul

Do you have backlash?
Hood

Are you referring to mechanical backlash.
like play in the drive gears ?  i will check to see if there is any play there
can the velocity and acceleration setting cause this
thanks paul

I am not sure exactly what the issue is, it does look in the pic that opposite corners are much more rounded than the other two, is that the problem?
Hood

yes hood that is the problem.
the problem seem to happen when the bit goes around the corners
so i am not getting a clean rectangle.
i seem to have this problem anytime i am cutting out a small area.
if i was cutting out a 12x12 area its ok.
it seem as if as the bit picks up speed on the 1 inch side it then suddenly does int the curve  and that is what cause the problem.
thanks again paul
my backlash is set to 20 percent
shopbot cnc stepper motors

Not sure on backlash settings with the PP as I have never used them but certainly seems like backlash to me.
Hood