I scuffed up one side of the access plates (definitely easier than waiting until priming day after everything is dimpled), enlarged the holes to match the screw size, then dimpled and deburred the edges. I won't need these parts until the very end of assembly and paint, but at least they're done. I'll just prime the inside the next time I do a batch of parts and then set them aside with the other orphan parts.
Back to the spar and a few more nutplates. These go on the inner portion of the spar as part of the connection to the center section in the fuselage. I don't think I'm going to actually build both wings at the same time just because of logistics of space, but so far I've done the spars in tandem. It's just easier to set tools up once and do both spars together.
Next I needed to fabricate the tie down bar. The basic form is supplied, and thankfully they've already reamed a hole down the center of the spine. I don't have a tap though, and Home Depot didn't have any sets in stock, so that task will have to wait until I get a set shipped.
The aluminum bar needed holes match drilled to the spar. I started with one hole located per the drawings, then lined everything up on the spar, clamped it in place and drilled out the rest with the holes in the spar as a guide. With each hole I slipped a bolt in to make sure the part didn't wander as I kept drilling holes.
I want to be able to attach these to the spars and be done with it, so I grabbed the rattle can primer and primed really quick. I still can't get over how awful smelling that primer is. It really makes me appreciate the Stewart water borne stuff, which is almost odorless. I'll wait to attach these until I've tapped the hole for the tie down ring.
With that, the front spars are pretty much ready to go for wing assembly. I stowed them back in the crate and pulled out the next batch of parts. Next up is the rear spar, which is much different in approach than the front. The rear spar is a thin aluminum Z shaped channel that gets a number of doublers on it, just like the spars in parts of the tail. Of course, these are double the length. Once again, I grabbed both right and left sides to tackle both at the same time. All of the doubler pieces had pretty rough edges - they are about 1/8" thick, which I'm guessing plays a role in how clean they can be punched. At least these look punched. I don't think they are laser or water cut. I hit most of the parts on the sander first to get rid of the big tabs left on the edges, then smoothed everything out on the Scotchbrite wheel. For the inside edges I used a file, followed by sandpaper.
I didn't get around to deburring edges on the spars themselves yet. I'll probably wait and do that after I've match drilled everything. Other than that though, these parts are ready to start initial assembly and match drilling, which I'll probably get rolling on tomorrow. In the meantime, I need to plan out my wing jig, which is a couple of posts mounted vertically to the floor/ceiling and a metal angle iron shelf for the spar to rest on. I think I can actually get all of the way through clecoing and match drilling the main ribs to the front and rear spar before having to move everything to the wing jig though.
Once I'm ready for the jig, which isn't too far in the future, I'll have to kick one of the vehicles outside. The jig has to be pretty rigid, and since I can't go from floor to ceiling because of the garage door, I think I'll have to build a base on each end with plywood and 2x4s, stick them to the floor with a few dabs of construction adhesive (that may not actually be necessary), and brace a 4x4 vertical post. From what I've seen, the post really doesn't need to be any more than 4-5 feet tall. Something like this (from Smitty's RV site - a fantastic site I reference all the time):
I was done for the day after deburring all of the rear spar parts. Or, I should have been done for the day. After sitting down and updating the blog, I had a few minutes, so figured I'd just go out and start match drilling a few parts. Two of the doublers are just blank pieces of aluminum with a flange on one side. These get placed on the spar and match drilled. The flange on the spar was almost a perfect 90 degrees though, and the doubler's bend was off by a good 10 degrees or more. That should have been my clue that I had something wrong, but instead I figured it just wasn't bent quite right and I "corrected" it. I clamped everything together and match drilled.
Just as I finished the last hole, it hit me - I wonder if the top and bottom angle on the spar flanges are different since the top and bottom of the wing obviously have different shapes. Yep, they're different, and the doubler flange would have matched up perfectly with the other side. There are only a couple of holes in the other end of the spar that give a clue as to which side is up/down, and I had it wrong, so I match drilled the part upside down. At this point I should have known that if something doesn't fit perfectly, I probably have it put together wrong. The good news is that I have a second doubler for the other wing that I can use for this spar while I wait for a replacement. At least I screwed up a cheap part ($9)! I keep a running list of things to buy from Van's, so I placed an order for the doubler and also some safety wire and tie down rings.
