Ribs

[TheDeltaFox 0]

Has anyone here experimented with putting a layer of fiberglass or carbon fiber over the trailing edge hangar ribs? I was thinking that while I have the wing opened up i'd put a layer of carbon fiber on each of the ribs to protect them and strengthen them against any accidental side load such as what snapped my two outboard ribs.

Any thoughts?

[dholly 718]

Hehe, we ain't got no fancy Carbon Fiber over at the Shoestring Skunkwerks! I just made up some flaperon rib tail stiffeners out of scrap aluminum. If I were to do it again I would extend then stiffener right through the lower capstrip and Hysol + rivet to the interior rib web as well. I coated the wood everywhere under the stiffeners with Hysol to prevent moisture retention and wood rot.

[TheDeltaFox 0]

I like your idea!! I have a bunch of 0.25 and think i may just copy cat you. Are you using small bolts to attach each one or just some pull rivets?

This is the reason why this forum is awesome. Thanks again,

Darcy

[akflyer 1427]

I would flip those over so that water could drain out the bottom side and have the solid cover on top. When I rebuilt mine, I put he aliminum on each side as shown in one of the S.B's. I used hysol and prepped the hell out of the aluminum. I put hysol on each side of the rib and then put the aluminum on, then stacked the ribs and put waxed paper between each set. I then clamped them in the vise to squeeze out all the extra hysol and left them there overnight. A few days later I could peel the aluminum off very easily. I ended up with one wing having the re-inforced rib tails and the other wing does not have them. I just coated the hell out of them with Spar varnish then epoxy primer. I am sure that one day soon (since my plane sits out in the weather) I will end up wicking thin super glue all along the top side of the rib tails to keep them from getting any water intrusion.

[dholly 718]

I just pulled (4) standard cherrymax rivets at the hole locations shown and clamped the tip to squeeze out the extra Hysol. When it was dry I drilled out the rivet heads and ground off the tails, then filled over the holes and top of the rib tail with some Bondo and painted everything for a nice smooth look. I agree with Leni that I should have flipped them over but, hey, mine was destined for a more cushy under cover life.

[TheDeltaFox 0]

I got my new ribs in the mail and the cap strip runs right to the end of the hangar for more strength. Anyone have any suggestions for removing the cap strip from the existing rib so i can put in the new splice in?

[dholly 718]

Here's how I did it...

[TheDeltaFox 0]

Question... Why didn't you or couldn't a person leave the cap strip running to the end of the hangar and just round it off? It would make it a lot stronger to side load which is why mine broke. Well that and a shoulder from the guy who fell off the ladder and into the flaperon.

[Russ. 7]

Question... Why didn't you or couldn't a person leave the cap strip running to the end of the hangar and just round it off? It would make it a lot stronger to side load which is why mine broke. Well that and a shoulder from the guy who fell off the ladder and into the flaperon.

Thats how I do it. I trim along the sides of the tail and leave the cap strip on the tail. Russ. N844RS

[dholly 718]

Question... Why didn't you or couldn't a person leave the cap strip running to the end of the hangar and just round it off?

1.) That was how my Mk-IV manual said to do it.

2.) It facilitates installation of the metal trailing edge and, IMHO, provides a 'shoulder' to catch the metal which helps prevent 'oil-canning' and keep everything straight when shrinking the fabric.

I would add that the construction manual for early Avids with the trailing wire (aka. the 'batwings') and some C models DID instruct to leave the capstrip at least partially intact all the way to the rib tail end. It called for tapering the top capstrip width wise, beginning at the trailing edge wire (full width) to the end of the rib tail (web width) using a straight taper. I believe the change in construction method came with the Mk-IV manual.

But, of course, it's all Experimental so do as you please!

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[edit] P.S. Russ , kinda hard to see exactly what you did in that wing pic from www.wingtanks.com, do you have a better pic?

Edited 25 Aug 2011 by dholly