Hi Ian, just trying to make a simple box with mitred edges, I definitely underestimated how difficult this was going to be. Your analysis is pretty close to the mark as some test bits seem to be fine, others aren't. I assumed that the timber was straight and true as I ran it through the jointer and the thicknesser but on measuring it again there are variations in the thickness. In regard to the shot end being at right angles, I'm using a clamp at one end so that I can fine tune the angle but no one setting works for all the test pieces so far.