Riveting the Leading Edge January 29th, 2008
I discovered that by using a bit of masking tape on the rivets, not only do they stay in place as you rivet, but it also keeps the skin from getting marks or scratches from the rivet gun. Before, I would put masking tape on the rivet set, but it starts desintegrating after a couple of rivets, and it is very hard to take off. By putting the tape on the rivet, the rivet set stays clean and it comes off very easy later.
It took me a couple of days to get all the rivets. Here is the finished product:
Countersinking Spar Rivet Holes January 21st, 2008
Before fitting the leading edge again for final assembly, I countersunk all the holes where the leading edge attaches to the spar. The construction manual doesn’t really talk about this, but the leading edge skin holes have already been dimpled, so in order for things to fit tightly, these holes need to be countersunk (the spar is too thick to be dimpled!!!)
The task is very straightforward — just set the correct countersink depth and start drilling. The only thing to be aware of is that the countersink depth will change slightly depending on how hard you push, and may even drift just a tiny bit over time. I used a rivet to check for the correct depth every four rivets or so.
There are 65 holes on each side of each spar, so that’s total of 260 holes, just for the leading edge. There are a few hundred more where the main skin attaches 🙂
Priming Leading Edge Ribs January 13th, 2008
I have put both fuel tanks away, and I am ready to go back to the leading edges. I spend all day today priming the ribs and skins. I am still using the Stewart Systems water-based primer.
The wing jig was briefly converted into a rib-holder. I draped tarps on both wing skeletons to keep paint from getting on them.
After speaking to an AFS rep at Oshkosh last summer, I am going to wait for about a week until I start putting the leading edges together. Given the relatively cold weather, this should be plenty of time for the primer to harden.
Dimpling Leading Edges and Tank Skins January 4th, 2008
Normally, you would use a similar C-frame, but instead of using a handle, there is a shaft you whack with a hammer…painful and easy to put a hole where you don’t mean to. This thing is very easy to use. Just put the skin on it and pull down on the handle. I did both leading edges and both tank skins in two short sessions.