Hey Dave,
the information on the working area of a CNC machine always refers to the coordinates that the machine can move to, as the additional bit radius is not known when selling the machine. To be more precise, it is also not a working area, but since there are three dimensions, a working space.
In the case of the Woodworker machine, it is 816 x 816 x 133 mm (163 mm with Z-20 slider) for X, Y, and Z.
You get a “no fit” error if one of your g-code commands want the machine to move to a coordinate outside these three-dimensional coordinates. They are defined in the corresponding MOTORS pages under ‘min-soft-limit’ and ‘max-soft-limit’. When loading a g-code program, the Onefinity checks the program for fit.
In fact, however, the area that you can mill is larger, as you can see here, because the bit radius can be added on all sides.