elevator skins

[IWayman]

Hi Everyone,
I'm looking at reskinning the top skins of both my elevators (and flaps too eventually) on my 170B and wondered if anyone has done this.
My questions would be...
Who has the best fitting skins available? Is there one source more recommended than another?
Did you build a fixture for the elevators when you re-skinned them?
What is the best sequence and method for riveting them back together?
Thank you,
Ian Wayman
N1888C

[jonesronc]

No experience with elevator skins, but I did my RH 180 flap a couple weekends ago (I'm A&P). No jig, took 16 hours or so by myself, not counting painting and priming (which were done before assembly), but including removing and installing the flap. I used McFarlane skins, took the top skin off, used it as a guide to drill the new skin, riveted it onto the spar and ribs except for the far aft rib and outboard rivets, then removed the bottom skin. The top skin was no longer close to matching the corrugations of the bottom skin, so I fabricated some .025 2024 hole finders using countersunk -3 rivets to poke into the spar/rib holes and match drilled the new skin, taking care to align the corrugations. I used a small rectangular tungsten bucking bar (http://www.tungstenbuckingbars.com/dime ... ETBB14.pdf) except for the aft rib rivets, for which I fabricated a 12" x 1-1/2" x 1/4" steel bucking bar (I've since ordered a custom tungsten one - $199; steel was a little light - I think my fingers are still vibrating). For the bottom skin inboard and outboard rivets, I used -4 Cherry Max ( a total of two), because it's really hard to get in there without eyes on as there are some -4 rivet shop heads making it hard to get the bar in there, and I didn't want to have drill those out and replace those as well. I used -4 for the spar rivets, except for the inboard/outboard two, which I had to redo because of the previous sentence, which were -5. The ribs and trailing edge were -3. I used a pneumatic squeezer for the trailing edge; tilting the squeezer so that it squeezed the rivet 1/2 way between the upper and lower skin angles. A little trimming on the inboard side with a 2" sanding disc. Turned out pretty well; very slight wave in the trailing edge at one point, barely visible unless you look very hard.

That's all I got off the top of my head; HTH.

[jonesronc]

Oops, I forgot I have pictures online: https://www.flickr.com/photos/129286532@N02/