Today I began to work on beefing up the outer end of the left elevator trim tab spar (E-606PP) by tying it into the E-720J Stiffener. You can see this in the diagram below. Unfortunately when I started this, I didn’t have too much in the way of guidance or direction. Just that it would be good to strengthen this area. So here we go…
The First Attempt:
I started out by making an angle that would be riveted to both the E-606PP trim tab spar and the E-720J stiffener. Since the stiffener is tapered, I would also have to taper the new angle. To make a long story short, the more I thought about it, the more I didn’t like having to try and rivet this angle onto the tapering E-720J stiffener.
You’ll also note that I have a scrap piece of 0.025 aluminum under the angle. This is just to space it up off the skin which I don’t want it rubbing against.
Here are some pictures.
Access to this area is also a bit tight. I used some lockwire to hold the skin back and used a scrap piece of wood to help hold the skin open.
This first attempt at adding an angle to this area was soon abandoned. I sent Mark Frederick a few pictures of this and after some discussion I was soon off to plan B and a second attempt.
Plan B: Second Attempt
On the second attempt I have a whole new approach. This time around I started with making new stiffeners to replace the original RV-8 E-720J parts. The idea here is to have 2 stiffeners mate back to back to eventually for a E-720J rib. These stiffeners will be riveted together during the final assembly of the elevator. This new rib will provide me with greater surface area in which to have the angle tying the E-606PP trim tab spar and this rib attached.
Here is a picture of the new F1-E720J stiffener and original RV-8 stiffener.
Here are 3 views of the new stiffeners installed in the elevator.
Now that these new stiffeners form a rib, it makes it easy to have the stiffener angle tie the E-606PP trim tab spar and E-720J stiffeners together; again, really beefing up this area of the left elevator.
In the next picture you can see where the stiffeners will be riveted together.
Please comment, I love to hear from my readers. Thanks again for coming along for this ride, you make my work worthwhile.
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