OP38 – Aileron Trim

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I wanted to do the Aileron Trim work prior to attaching the bottom wing skin.

A few parts to deburr … oooh, goodie! I’ve been missing it!

Having chosen an access plate, & once positioned, the Trim Actuation Assembly is match drilled.

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The manual says do all this once riveted, but I wanted to final drill the holes prior to priming.

The holes in the trim servo are match drilled into pilot holes in the assembly.

I assembled all the components to ensure correct geometry.

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After priming some easy riveting for once.

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I haven’t worked out yet the logic of the wire routing … it comes out of the side through a bush, and then into a Molex Micro connector which in turn is located in the assembly side … so the wing wires will have to go inside the assembly to get to the Molex.

I guess it’ll become clear??

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Nutplates complete the assembly.

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I used a 9 volt battery to run the servo to full deflection each way, and then positioned it back to neutral ready to mark the aileron pushrod.

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Having screwed the access plate into position, and set the aileron pushrod to the neutral using the template, it was an easy job to mark the trim neutral position.

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Having clamped the pushrod into position using a set square on the rod end, I used another set square to mark the centreline of the spring brackets on the perpendicular.

I checked several times I was about to drill the holes in the correct place!!

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I drilled the first holes having marked them using a centre punch …

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… and then clecoed on the brackets.

Since I couldn’t work out a way to clamp the brackets firmly, I centre punched again to help stop the drill bit from wandering.

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This seemed to work well.

The spring brackets are riveted with LP4-3’s : )

See here for a method to attach the springs!

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2 Comments on "OP38 – Aileron Trim"

  1. Jack Billington | September 28, 2022 at 9:44 pm | Reply

    How did you install the springs to the servo and tube? Do you have photos showing that task?

    Thanks. I have used your notes many times to assist me in my build!

  2. Hi Jack, I’ve been meaning to add this topic to the blog, and your question has reminded me! Please see here … https://vansrv14project.uk/2022/06/05/op38-aileron-trim-springs/

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