Archive for the ‘Pitch Autopilot Servo’ Category

More Empennage Fairing Work – 6 hrs

March 25, 2012 Leave a comment

Sunday Mar 25, 2012

Fiberglass work is not my favorite, but is has to get done. I finished trimming the empennage fairing and I drilled all the holes that attach the fairing to the strutcure and then I drilled the holes that will have #6 nutplates to #27. Fortunately a 1/8 inch cleco works fine in a #27 hole.

Along the longerons I drilled the holes out to #36 to be tapped for a #6-32 thread and on the aft end I had to drill out two more rivets.

I plan to use tinnerman washers on the fairing so I countersank the holes accordingly.

I sanded the edges and the entire outer surface of the fiberglass to prepare it for priming. I’m expecting pinholes in this thing so I plan to use several coats. I did not have to cut and patch the fairing on the right leading edge because I was able to shape it to a snug fit using a hot air gun. I just warmed it up until it got soft and I pressed it into contact with the leading edge using the end of a socket wrench extension until the material cooled.

Then I removed the pitch autopilot servo motor from the fuselage and I installed a 9-pin D-sub connector along with some woven braid to protect the bundle.

Pitch Autopilot Servo Install, Part 1 – 1.5 hrs

March 22, 2012 Leave a comment

Thursday Mar 22, 2012

After three days of curing the Proseal was finally firm enough that I could rivet the NACA vent scoops to the fuselage skin. Four rivets per side and they are done!

Then I started preparing the autopilot pitch servo for installation. First thing was assembling the pushrod per the dimension in the Dynon instructions. Then I mounted the pushrod to the elevator bellcrank. It was much easier to do that on the bench because you have to slide an AN960 washer between the two halves of the bellcrank to keep from bowing the plates when you tighten down the nut.

I put the bellcrank back in and mounted the servo motor, then attached the pushrod to the motor crank arm. Everything seems to work fine. I may adjust the pushrod a little longer because it looks like the center of the motor travel is off a little from the center of the linkage range. I will also remove the motor again to install a 9-pin connector because that is easier to do on the bench also.

I also did some more trimming of the empennage fairing and I drilled all the holes into the vertical stabilizer with a #40 drill. All these holes with clecos will be drilled out and countersunk for a #6 screw with a Tinnerman style washer.

The fit on the left side at the leading edge is actually not bad. I think I could live with this.

The right side is not as good however. That lower lip does not fit tight against the leading edge and would create extra drag. I will have to do some more work on that region.