One thing I have learned about drilling out steel pop rivets - avoid it all costs! Anyway, more on that later. Here is the elevator with trim tab in position - no more clecoes holding the hinges or the riblet - everything is riveted.
Next is a close up showing the pop rivets now holding the riblet on the elevator (left side of pic), and the gap required between the outboard edges of the elevator and trim tab (3/32")
Next is a shot of the clean line on the top of the elevator with the trim tab in the neutral position. After all the careful measuring and re-measuring and trial fitting, sure is nice to see this come together. While it has taken me a long time to get to this point, I am still glad that I have only had to make one trim tab, while others that reach this step sometimes have to make two or three before they get it right.
And a nice rivet line of flush rivets attaching both halves of the trim tab hinge to their respective parts....
I used the hand squeezer again with the standard 3 inch yoke, with the small 1/8" x 3/8" wide flat set for the shop head (minimum interference with the hinge eyelets), and the 1/8" x 1/2" wide flat set on the other side - same way I did the hinge on the trim tab. I was still really concerned about not having enough clearance for some of the eyelets, since some of the rivet holes are directly behind an eyelet, but between the thckness of the two 1/8" thick flat sets, plus the gap required between the sets to create the proper shop head, you really don't have to worry about it too much. Just go slow and make certain you do not apply any undo pressure on any of the eyelets and it works out fine.
The hinge pin sticking out of the end is part of the temporary hinge pin they provide in the kit. You get the proper length hinge pin in the fuselage kit for some strange reason. The end of this pin still has to be bent and either safety wired to the E616PP trim tab spar on the elevator, or secured by using an eyelet taken off of a piece of hinge (I will probably do the latter). For now you just use the temprorary one to get it all lined up and installed.
Next is the fiasco with drilling out the pop rivet on the bottom of the trim tab. Truth be told, both of them were sitting a bit proud of the surface, but after all I went through just to drill out one of them, I am totally fine with leaving the other one completely as is. No matter what drill bit I tried to use, I could not get this rivet drilled out to save my life. And the standard method for solid rivets, which is to drill the head out and then snap the head off - Haaaa! Forget that. The rivet already has a hole in it from the mandrel going through the center of the pop rivet, so the edges are already shallow, and this is a hardened structural pop rivet that will not break away like the solid rivets do.
So the things I learned from posts on VAF if you ever have to do this are: take a small diameter punch and drive it lightly with a hammer through the existing hole oin the center of the rivet until the bottom (round part) of the mandrel comes out the other end, then take the drill and drill out the rivet.... simple - right? Not really.
I think I finally reasoned that I needed to use at least a 7/64 inch drill bit to drill out the rivet, because that is what I had to use to widen the original rivet hole for the pop rivet. You pretty much have to drill out this rivet by drilling through the sides without enlargening the hole. I ended up getting the head to lift out of the hole just enough to get a pair of small needle nose pliers on the head, and I tried crimping and twisting the flanges of the head off so I could then punch the remaining part of the rivet out of the hole. It ended up requiring the combination of drilling out the rivet with a larger drill bit (7/64"), and then prying off as much of the rivet head as I could, without damaging the trim tab skin, and drilling some more until I could put a punch in the hole and drive out the remaining portion of the rivet.
I finally got the dang thing out, and much to my surprise did not enlargen the hole too much, but it was still widended enough to cause me some initial concern about setting another pop rivet in the same hole. I decided to go ahead and try it again after trial fitting a new pop rivet in the hole, and I realized that all that work to get the rivet out actually deepened my dimple just enough to allow the rivet head to sit nice and flush in the skin. The rivet grabbed the riblet and the skin pretty much the same way that the first one did, so it turned out to be a nice tight fit. This next pic is the remnants of the pop rivet that I had to drill out. there is the round mandrel tip that had to be punched out, the rivet shaft, and a small piece of the rivet head that I managed to pry off with the needle nose pliers....
Moral: Avoid drilling out pop rivets if at all possible - the structural pop rivets are a pain in the ass to get out.Perhaps if I practice removing them I will get better at it. This whole process brought back very bad memories from working on the horizontal stabilizer and messing up rivet holes, requiring a major structural repair after the fact. Fortunately this experience turned much better than that one.
And finally some pics showing the nice streamlined trailing edge one from the outboard side and the other from the inboard side of the elevator - still looks very nice, even after all that mussing and fussing and fiddling with the parts all this time....
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