First main assembly completed - at a cost!

Monday 24th March 2008 (7hr)

Riveted R-HS top skin. Riveted inner H904 tip rib on left HS. Replaced rivets on inboard left HS rib-spar-shim-inner nose rib join. riveted outboard right HS nose rib to spar. Riveted in left HS inboard/outboard main rib. Riveted rear spar to skins and inboard/outboard main ribs.

Dorothy joined me again today to finish out the riveting of the skins. We did the right HS top skin and went back over any rivets that did not pass muster.

At this point I made one of my regular screw-ups. I riveted in the inner main ribs, beginning with the skin-rib rivets along the inboard edge of the skin . What I should have done was to begin with the nose rib-spar-shim-main rib rivets while the main rib was still mobile. The reason is that the main rib is angled inwards towards the aft end and it is very hard to get access to its forward flange. If the aft end of the main rib can be pushed back to a 90 degree angle or beyond, it would be easy to get the air squeezer in here, at least with a longeron yoke. As you can see from the first photo, I tried to access it with a double offset rivet set in the gun. This worked okay on 5 of the six rivets (though it caused a lot of scratching to the primer and one or two of them had to be done a second time). However that last rivet in the corner just wouldn't set right. When the third rivet in the same hole bent over, I abandoned it and put a rivet in a new hole right next to it - leaving plenty of edge distance.

What annoyed me most was that I had two chances to avoid this problem and missed both of them. Of course I should have followed the Vans assembly sequence more closely in the first place but, when I came across the difficulty in accessing these six rivets, I should have bitten the bullet and drilled out all the skin-rib rivets to go back to the Vans way of doing it.

I will have to see what the inspector says but if he agrees with my fix then at least the entire unsightly area will eventually be covered by the emp fairing. In the meantime, it is going to be staring at me for the rest of the project and saying "BE VERY CAREFUL IF YOU DEPART FROM THE VANS MANUAL".

Perhaps I should not have done it but I went on and riveted in the aft spar, which carries the elevators. This requires more pop-rivets into the aft flanges of the internal main ribs and solid rivets to the inboard and outboard ribs as well as the trailing edge spar-skin rivets. All of these were easily done with the air squeezer but I was not enjoying the process because of my black mood and barely celebrated the completion of the first recognisable part of the aircraft.