First, Build a Shed

[Cherrybark]

While talking to either Debra or John I learned Kitfox sells a mounting kit for Garmin Auto Pilot Servos. As you would expect, the kit comes with an inventory sheet and the usual collection of labeled bags of parts - right down to a two tube, hand injector of Hysol.

With this kit you can completely avoid headaches from fabricating brackets, ordering rod-ends, and trying to figure out how to mount the servos. Both servos connect to idler arms with bushing as standoffs between the rod-ends. It took about two hours to inventory parts and test fit the servo brackets.

The only nagging concern is the pitch servo is mounted in the tail of the plane, just forward of the rear elevator idler arm. My plan was to cover the fuselage before installing instruments. It's going to be seriously aggravating if that servo doesn't operate.

[efwd]

Wow! Thats Clean. Wish I had asked John about mounting. I spent hours fabricating and fitting my servos which may look like crap to some but their in and accessible. I certainly never thought about mounting them further aft thats for sure. Easier.
Eddie

[Cherrybark]

I'm confused by the manual drawings of the cuts in the Tail Access Covers for the airfoiled tail.

I assumed the final plates will have cuts with backing strips so an access plate is removed from the tail buy unscrewing the nuts around the perimeter and gently bending the plate and slipping the stabilizer and elevator tubes through the cuts in the plate.

Surely I'm reading the drawing wrong but Final Assembly Page 61 shows the rear cut extending fully across the access plate with the backing strip only covering the bottom half of the cut. On page 63, the aft hole in the access plate shows a cut from the bottom of the plate, the continuing cut to the top is gone, but a new cut extends to the rear of the plate. In both situations a section of the access plate will be completely cut off.

The cuts for the Standard Tail make more sense. Each hole has a single cut running from the hole to the edge of the plate, with appropriate backing plates.

To add to my confusion, on page 59, the pattern for the backing plates shows rivet holes drilled on either side of the length of the plate for a total of six holes. The instructions for mounting the backing plates call for six rivets to secure the backing plates to the access plates but the drawing only shows three rivets per plate. Surely you don't rivet the backing plates across the cuts. Doing this would require drilling rivets to remove the access plates.

Clearly I don't understand this assembly. And the process has become like one of those optical illusions. Once you see it one way you're stuck until someone points out the oddly shaped candelabra is actually two faces looking towards each other.

Does anyone have pictures of these completed parts?

[jiott]

Carl, Yes the drawings are confusing and not correct. The backing plates on page 59 show all holes, but only one side is rivet holes, the other side is holes for the self-tapping screws you will use. Page 61 is not correct for the airfoiled tail. Use the cut pattern shown on page 63. Don't use the standard tail pattern; it will require way too much bending to get on and off. The pattern on page 63 shows two cuts at right angles to each other; the backing plate only goes on the vertical cut. The horizontal cut doesn't really need a backing plate to stay in position, although I suppose you could put one there if you wanted, but in my experience it is not needed. On the very rear where the access cover screws onto the fiberglass fairing, I highly recommend you reinforce the backside of the fairing with a strip of aluminum (just use Hysol to attach it). This will give those screws something more substantial to tap into and help avoid stripping them out during your frequent removal of these access covers every annual.

While I'm spouting off on suggestions, make sure you put a round inspection cover on the belly of the airplane right under the elevator rear idler arm. Every annual you need to inspect and lube the ball joints and a cover makes it easy-peasy. Wouldn't hurt to also put one under your rear AP servo maybe.

[jrevens]

I used little Tinnerman clip nuts around the perimeter of those panels - I believe they were included in the kit. I used some slightly different ones on the rear 4 holes. Then I used some "Tric-nuts" on the steel tabs that are welded to the fuselage. It would have been just as good to use the clip nuts there too. So, those little SS screws have a replaceable "nut" to screw into. I can post some pictures showing how everything went together for me if it would be helpful, Carl.

[Cherrybark]

Thanks for the quick answers and suggestions guys. Reinforcing the fiberglass is obviously a good idea and I wouldn't have thought of it until the holes weakened. And now I know the real name for those "clip nuts thingies".

Definitely need an inspection plate under the AP servo and I'll remember to put another under the idler arm. While I'm taking notes, what lube do you use on the ball joints?

Pictures would be great John.

[PapuaPilot]

Almost everything in the Kitfox is lubed with LPS-1. That will work on the Hiem ball or rod ends (ball end thingies).

Another lube that I like even better is Triflow, we use in our shop. It is a Teflon based lube.