Because I swear nothing in my shop is. On the quest for a flat trailing edge on my rudder....
I first match drilled my 1.5 in aluminum angle to one of my skins. The rudder skins were very thin so instead of running a bit, I clamped the skin to the angle and used a 3/32 punch. By rotating the punch I was able to create a perfect circle imprint on the angle. I then went back with the skin removed and center punched every hole imprinted.
I drilled each hole in the aluminum angle #30 instead of #40 so it wouldn't create any waviness if my holes weren't perfect, Silver Clecos will hold in a #30 hole, especially wedgelocks. This helps keep the angle as a flat reference, not as a locator for the holes.
I then clecoed the assembly together with both rudder skins and match drilled both skins and the wedge perpendicular to the chord line of the wedge. I did this freehand. I started in the middle and worked out, clecoing every hole as I went. Disassembled and then countersink each side of the wedge perpendicular to each side face. I did this with metal rulers and a square clamped to the drill press, while being sure to keep the wedge flat while drilling. Broke the edge on both rudder skins. Dimpled the skins.
I used the adhesive 3M tape recommended by Vans in the -14 manual. I bought a 5 yard roll for $5 on Amazon. I taped my angle to my worked bench, held up with washers. The aluminum angle actually wasn't completely flat so I used aluminum sheet and nuts underneath the angle to both make space for the clecos and shim the angle completely flat. I used tape to attach that to the bench.
I then 3m taped both the right rudder skin and both sides of the wedge (3 layers at this point). I placed that down and ran 5 clecos the entire edge through all three sides of the tape. Removed all 5 clecos. After that I removed the backing from the bottom of the wedge and skin, and placed the wedge very carefully replacing each of the five clecos until the wedge was attached, with backing still on the top side.
I then had a friend help me lay down the trailing edge and cleco while I put in the pop rivets to attach the stiffeners. We would carefully remove the backing from the top of the wedge as we worked our way towards the top clecoing every hole of the trailing edge.
Well its totally straight and closed so far! My friend and I agreed that really how I do riveting will determine how straight the rudder will end up, but at least I have a good reference before I start riveting. (I also had to peel back the bottom 3 or 4 clecos to I could lift up the edge and hit the last 2 rivets in the very bottom stiffener with the no hole yoke, I did this as quickly as possible, see photo)
I am going to finish off the rest of the rivets around the edges tomorrow and rivet the trailing edge this weekend maybe. Giving it a few days to set can't hurt, plus I have to go back to work.
I am a little unsure how exactly I am going to rivet the trailing edge. I am thinking right now I am going to try and use my pneumatic squeezer to just barely set rivets in the order recommended by Vans and then use mushroom set and back rivets plate to finish. When I get to this point should I used the mushroom set in gun on the manufactured or shop head? I could see it working either way. Would using back rivet set work better or just mar the skin due to the smaller diameter?
I hope my explanation of how I figured it out helps someone out. If anyone has an advice on how to improve my method feel free to add, I have the elevators next and am open to suggestions!