Wingtip Pillowing

[Yadama]

Hi All

I am in the process of installing wingtips and have completed the left side however there is significant pillowing between the screw attach points which are spaced at 7.5 inches. Has anyone else experienced this and if so what is the solution?

[Battson]

Yes, that is perfectly normal depending on the exact shape of your wingtips. The fibreglass ones see to be tapered outward at the sides, so they all do that bulging / pillowing thing.

Adding more screws will reduce the problem a lot, 3 or 4 inch centres seems to do it.
You want to use countersunk screws with wide area washers, or they look unattractive. I only did this on the bottom side, because you never see the bulges on top.

[Flygirl1]

That bulging thing drove me nuts! I've seen it on Husky's and other planes and I hate it. We bent the edge inward all the way around so that the fiberglass would lay flatter and we trimmed the fiberglass and had it as close to the edge as we could. We also used large slightly domed headed rivets. I agree with Battson, flush would look nicer, but by the time we got to doing that we both had enough of counter sinking, and putting in nut plates. We figured we could drill out a rivet as fast as we could take out all those screws and I think these look pretty good actually, but if I had to do it over again, I might go with the screws. There is a spot on top of my wing where that darn pop rivet gun got away from me and skipped across my paint all the way through to aluminum.

[JimParker256]

That does look really nice. You guys did such a great job.

[Flygirl1]

Thanks Jim!! ;-)

[Flygirl1]

I measured these and they are 3 in on center. D.

[Yadama]

Thanks for the assistance Guys and Gals

Has anyone had a problem where the wing tip is too short and needs to be extended?

[Mark Goldberg]

Yes. I had to extend my wingtip aft about 1/2". Check to see if the outboard trailing edge rib that the wingtip attaches to could be re-positioned. Sometimes that helps. Mark