Left Wing - Riveting

It feels like it's been forever, but I finally got my new rivet set and got some work done on the plane tonight!  It's amazing how big of a difference this rivet set made.  It's just 3 or 4 inches longer than the other straight cupped set I have, but it was night and day in terms of how easy it was to set the rivets and how much nicer they ended up.  The other long set I have is the offset angle one, and it's a last resort option for me at this point.

Along with the rivet set, I also bought some plastic covers (the orange piece on the set) that a few people had recommended.  These are just a thick piece of plastic with a hole in the end that are supposed to help keep the gun centered on the rivet and keep it from bouncing around so bad with the higher air pressure needed for the -4 rivets.  These were expensive considering they are really just a 1 cent piece of plastic, but in the end, they actually did make a big difference.  A bag of 10 will probably last me most of the build, so worth it.

There were a few things I noticed while riveting the ribs to the spar.  I'll have to do a little research, but the anodizing process must make a really brittle surface on the aluminum or something.  The pressure from the clecos is enough to leave an actual indention in the aluminum.

The other thing with the anodized surface is how it cracks when riveted.  For areas where there was a doubler on the spar, making it much stiffer, the rivets set normally.  For areas that were just the single layer of spar material, the anodizing kind of shattered in a star burst pattern around the shop head.  You can see it in the bottom two rivets:

One I got the hang of using the longer rivet set, things moved right along and I got all of the ribs riveted to the spar. 

That was followed by riveting on the rear spar.  All of these rivets could be squeezed, which was a welcome break.  I don't mind bucking rivets, but the larger 1/8" rivets are kind of hard on the fingers holding the bucking bar.  I've tried wearing a glove for padding, but I need my fingers free to feel how close the bucking bar is getting to the stock to know when to stop.  I may have to pull out my old fingerless biking gloves and gives those a try.

The rear spar was easy to do, but required a lot of back and forth with the plans, as well as setting and resetting of the depth of the squeezer.  There is a lot of variation in rivet lengths used here, but I think I got it all finished correctly.  I caught a few areas in the plans that show the rivets, but also call out that they are riveted in assembly with another part, so I had to leave those holes open until I'm ready with the additional pieces.

So the main skeleton is riveted together.  The next step is to move my wing jig into place and finish setting it up to hang the main spar on it.  Then it'll be time for the 10,000 holes of the wing skins.

One other thing that hit me tonight that I'm going to have to look into:  I drilled 3/4" holes to accept wiring conduit, but it looks to me like the other holes in the ribs (by the front spar) are set up for only one pitot line.  That was probably the norm back when the RV9 was first designed, but nowadays the pitot system is also coupled with AOA sensors.  I believe that requires a second line from the pitot itself.  There is a second tooling hole in each rib that is too small on its own, but I seem to recall reading somewhere that people open that one up larger to accept the AOA line.  I'll have to do a little more research.  I wish I had thought of this earlier since it would have been easier to drill the holes before the ribs were riveted in, but it's not the end of the world.  The other option may simply be running the AOA line through the lightening holes.