Many people make the trim tab several times until they are satisfied with it, so as on the trim tab opening on the left elevator, I practiced making my bends on some scrap aluminum before I made the those on the trim tab itself. This procedure worked well for me, and I'm happy with how the trim tab turned out.
Prior to making the first bend, I sandwiched the skin between some angled pieces of oak and clamped them to my workbench. I used double sided tape on the skin to prevent the oak wedge from slipping while the bending was taking place. I made the initial bend with another piece of wood, which I used to push the skin down toward the forming blocks. After that was finished, I used my rivet gun with low pressure (approx. 10 psi) with a flush set to complete the bend. Prior to bending, I made a radius on the oak wedge upper edge, which allows the skin to from a nice radius rather than a sharp angle. My initial practice pieces had very sharp angles that would eventually crack. With the bottom side finished, the assembly was turned over, re-clamped to the table, and the process repeated. The same procedure was then used for the inboard edge.
With all the bends complete, the hinge was drilled and attached to the trim tab and later to the elevator. The trim tab motor and cover plate were assembled, and the control horn was riveted to the trim tab. A few of the rivets for the control horn near the trailing edge are a bit difficult to reach, so I riveted the control horn prior to setting the rivets in the trim tab edges. This allows the trim tab to be opened, which makes it easier to access the more challenging rivets for the control horn. With that step complete, the remaining rivets were set.
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| First bend is made around angled oak blocks |
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| Inboard edge bends completed |
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| Control horn riveted to trim tab skin |
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| Hinge riveted to leading edge of trim tab and fit to elevator |
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| Rivets set attaching hinge to elevator |
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| Trim tab motor assembly work |
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| Motor assembly completed |
