Brief Description: Drilled all center spar uprights
With the help of Joy, I back drilled through my center spar uprights that were clamped to a block of wood for spacing. This went rather quickly and very well. The next step of spacing the dual control uprights exactly 258mm apart took some more doing. Without cutting into a new sheet of plywood, I didn't have any scrap wood that was 215mm high by 558mm long. My simple solution was to make a square frame of smaller material and use it to hold that parts in their correct locations while drilling. The results were outstanding, as far as I can tell. I say that because everything is subject to some fluctuation when the rivets are driven or the bolts are tightened on the uprights. We shall see. Now all I have to do it to trim the corners from all the uprights and flange the holes.
Frame for positioning dual control uprights
Everything in place
Side view. Note that the uprights still need to have the corner angles removed.
