Rudder trim switch

I've been thinking for a while that I'd eventually like to add rudder trim to this airplane, similar to what other builders have done. I may not actually get around to putting a servo in the rudder any time soon, but if I at least install a switch in the panel and run wires back to the tail it will be a lot easier to retrofit later. If I decide to fly the airplane before installing rudder trim, I'll just placard the switch "inop".

I had a Ray Allen rocker switch left over from a previous project, so I located it and dusted it off. There's a spot just below the radio stack, next to the flap switch, that's just about perfect for it.

I measured and marked cut lines, then used a unibit to hog out most of the material:

Then I used a hacksaw blade (held with leather gloves) to make a roughly square hole:

Then I filed away at the edges until the switch fit through the hole. It's not the kind of perfect cutout that I'd have had if I'd thought to include it when the panel was being CNC cut, but the switch bezel hides all that.

Test fitting in the panel:

To allow me to adjust the sensitivity of the rudder trim, I attached a Ray Allen servo speed control to the lower flange of the center subpanel rib.

Here's another view. I'm sure this thing is nothing but an LM317 and a trimpot, but it's easier to buy one of these than to roll my own.

Anyway, at least I can run all the wiring now and make the airplane ready for a future upgrade. Maybe some winter when it's too cold to fly I'll build a new rudder with a fancy trim tab… it would be nice to have a choice between building and flying! The airplane that I'm sort-of partners in has been down for maintenance since March, and of course the RV-7 is still in pieces in my garage.