Wayne,Having got to the point of building the 12Pi horns and even cutting the side panels of 45"x45", my brother began to draw out the side panel layout on a cardboard to exact scale, from the old drawings that you had sent me.
After beginning to draw the motor chamber, starting from the top edge of the side panel at 8 17/32", all other distances of the motor chamber/horn foldings fall short by 3/4" compared to published drawings.
Added to this is the fact that the top panel (and in fact all other panels) mount inside the side panels and not outside of them. This would bring the whole internal assembly upwards by 1 1/2". This could make my construction anything but a 12Pi. The worry is compounded by the fact that correspondingly the bottom corners/edges of the motor chamber measured from the bottom end of the side panels measure an excess of 3/4" compared to published drawings ie., 22 3/4" instead of 22".
Further the inner folds of the horn near the top front don't seem to add correctly ie., the measuremnts shown as 5 17/32" and 5 23/32".
Is there some help I can expect from Wayne or any of the other Pi builders. Thanks.