I finally finished my elevators! These seemed to take me forever, I think the two months off for the bathroom remodel had an effect. But in the end, I am pretty happy with how they came out. If I ever had to do them over I am sure I could do it in record time. The learning curve on this stuff is steep.
One of the final steps, after months of construction, is to bend the leading edges. This is a hair-raising event after so much precision work. One must duct-tape the leading edge of the skin to a bar and twist it to impart the curved leading edge shape. The rudder was done similarly, and I did not enjoy that process. So I went to Vansairforce.com and found much smarter people who came up with a controlled technique for the process. I used a long iron pipe, drilled for a removable lever, and conduit clamps bolted to the bench. It worked great, although it still made me nervous.
To the left is a picture of me clecoing the control attachment brackets to the tabs. They were a bit of a challenge to rivet due to the constrained space in between.
Below are pictures of attaching the hinge to the elevator and trim tab. Once everything is drilled into place, the hinge is marked, cut and then riveted to the respective parts.
The pin is left long and then bent in where it will be safety-wired.
Aug. 29, 2015
Some pics of back-riveting the elevator stiffeners/ribs. Always my first choice of riveting.
I have the elevators waiting to go together while I await some more rivets from Aircraft Spruce. In the meantime I started on the trim tabs. They are almost there too.
And pics of using small head NAS 1097AD rivets for attaching the nutplates.....
These are a smaller head rivet, with the same shank size. Great for this application as otherwise the larger (standard) rivet requires the steel nutplate to be either dimpled or countersunk, both difficult tasks. The rivet doesn't take much stress vertically, mostly laterally from screwing in or out of the nutplate.
The below photo shows how much wider and deeper the head is on the 426AD3-3.5 rivet than the smaller NAS 1097AD3-3.5. It shocks me that I actually understand these numbers now.
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The elevator construction gave me my first go at access/inspection plates and the attachment thereof. There are two access panels (right and left) for trim cables. They are attached to a reinforcement plate via small steel nutplates to allow for a nice screw-on connection. These are rather stamped out and rather horribly threaded. I have had to re-tap most all of them, although not a big deal. My biggest dilemma is how to clean them up and prime.
I assume when the nutplates are stamped they are covered with some type of lubricant. This leaves an oily surface which I assume would be a poor surface to paint to. So my first few larger nutplates on the vertical and horizontal stabilizer I cleaned up by hand with scotchbrite pads and a wire brush. It was very time consuming and not a lot of fun. These smaller nutplates are very difficult to hold onto, much less get cleaned off well.
So off to the dental office, and I have a mini-sandblaster. A light pass on them cleaned them up perfectly, and then I took them home and sprayed them with my air-brush. Very nice surface and they should be bulletproof. I like it when things work. As seen below, the top is as supplied, bottom left after sandblasting, and bottom right after priming. Best I can do.
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Aug. 22, 2015
I made good progress this week on the RV. During the week I took some time each evening to deburr, scuff and prep each part for the elevators. On Friday I arose at 5 a.m. to get a good start before the heat set in. Fortunately it was a very overcast day, as I was prepping outside where I could slosh water around.
Each part (of about 70) was scrubbed down with Prekote, an aluminum prepping agent. Unlike alodine and others it is non-toxic, safe to use and I am very happy with the prepped surface. It leaves a rather dull appearance which indicates to me it does a very mild etch, maybe more. At any rate, after I got all my parts scrubbed, rinsed and dried by noon.
Saturday morning I again got up early and sprayed all the prepped parts with Akzo Epoxy Primer, like the other components so far. It is very toxic, and so I again donned my Tyvek suit and full face respirator. Got everything sprayed by 9:30, the DeVilbiss gun sure does a great job.
BTW, Julie and I did some errands after spraying, and when I got back a few hours later the epoxy primer was stone cold hard. I can't believe how fast this stuff sets.
So I went to work, and dimpling, riveting and assembly did not do any damage at all to the new paint.
Can't say as much good about my cleaning of my spray gun. In a hurry to leave, I did not perform an exemplary cleaning job of the spray gun. When I got back I got to spend an hour painstakingly cleaning off the remnants of cured epoxy primer. Not recommended. I won't be making that mistake again.
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Aug. 16, 2015
Time to get to work again! I had made a deal with my beloved spouse to finish our master bath remodel, and for some reason the plane was making more progress than the bathroom. So I knuckled down and we are 99% finished. Here is a peek:
We did most all of the demo, design, framing, electrical, plumbing and drywall ourselves. I did have contractors who helped with the drywall finishing, cabinets, shower glass, tile and granite. It was a huge project but turned out nice.
It cost me about 6 weeks of not working on the plane, but got me back in good graces with my sweetheart.
Two remote control skylights, air-jet tub, heated floor and many other ammenities. My princess is now content in her new bathroom, and has bid me farewell to work on the plane.
So......back to the RV!
I did sneak out a few times and work on the plane.....
June 6 and 7 I started seperating all the elevator ribs, deburring and polishing them. There were sure a lot of parts compared to the HS.
A couple of shots putting the elevators together. I found them interesting, a bit more complex than the previous parts. The upper left picture is so that you could see my pal Gerard in the doorway.
So by late June I had the elevators both ready, disassembled for priming.
August 16, 2015
Now I am back at it, and after cleaning up the shop, made the following parts:
The trailing edge of the elevator (and trim tabs) have foam ribs. I transferred the drawings, adhered them to the foam and cut them out on the bandsaw. Then used a sanding board to flatten them precisely to the line. Below are all the ribs finished, as well as six trim tab "clamping blocks" to be used to put the trim tabs together.
And lastly I cut and finished the counterweights for the elevators. They are lead and cut very easily. In fact, if too much speed is used for cutting they kind of mush and melt. Interesting stuff.
The ribs and couterweights were produced because I don't have time to prime the elevator parts yet. I am hoping next weekend provides an opportunity.
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