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Wing overhang of top spar

PostPosted: Mon Dec 26, 2016 7:00 pm
by samiam
Seeking advice from builders smarter than me:

As you can see below, my upper wing skin overhangs the main spar at the wing tip. I just want to make sure this is normal (because there is no overhang of the skin on the lower aspect of the spar). It also seems funny because the final rivet hole is too close to the end of the spar and would require putting a rivet into the angle at the end of the spar cap. FWIW, I have preassembled spars and predrilled skins, so I am guessing either it is correct or I have the wrong part. Thanks for taking a look!

https://drive.google.com/open?id=0B0U7g ... 2I5QzBWWm8

https://drive.google.com/open?id=0B0U7g ... nFsby1pZms

https://drive.google.com/open?id=0B0U7g ... GU1cFVFdFE

Re: Wing overhang of top spar

PostPosted: Mon Dec 26, 2016 9:09 pm
by kevinh
Yes, that is correct and desired. If you look at one of the plan drawings they show that overlap (sorry - away from plans and can't remember it). The overlap will also exist on the upper side of the leading edge skin and facilitates mounting the wingtip.

Re: Wing overhang of top spar

PostPosted: Mon Dec 26, 2016 10:44 pm
by samiam
Thanks Kevin. I have been looking for something in the plans to support this, but can't find anything in particular. Mine is a second hand kit so my 10 year old drawings may not have it. Anyway, the overhang perfectly matches the leading edge skin so I assume it is correct. Thanks for your insight.

Re: Wing overhang of top spar

PostPosted: Mon Dec 26, 2016 10:46 pm
by Rynoth
Seems right. The fiberglass wingtip actually fits INSIDE of the wing skin (kind of like a plug), so you actually need that overhang to secure the wingtip.

Image

Re: Wing overhang of top spar

PostPosted: Wed Dec 28, 2016 11:32 am
by samiam
Thanks for the help guys! Any thoughts on the second pic above, which shows that the last rivet from the skin would end up in the angle at the end of the spar cap?

Re: Wing overhang of top spar

PostPosted: Wed Dec 28, 2016 1:12 pm
by Bryan Cotton
Mike,
Review your skinning procedure. The aft skin clecoes to the aft spar. Then you transfer holes to the ribs. Then you transfer holes to the spar. Then you cleco the forward skin to the spar and to close the front skins you need ratchet straps and boards. I suspect that the location where you have the leading edge clamped is too far forward. You can't fit the forward skins first.

The CNC quality of the wing parts was by far the best of all the kit. If something is not lining up right you are probably doing something wrong.

Re: Wing overhang of top spar

PostPosted: Wed Dec 28, 2016 1:18 pm
by Bryan Cotton
In addition to what I said in the post above, Sonex has instruction sheets on wing skinning and tip install.
http://www.sonexaircraft.com/support/instructions.html

Look in the wing section near the bottom.

Re: Wing overhang of top spar

PostPosted: Wed Dec 28, 2016 1:26 pm
by samiam
Bryan Cotton wrote:If something is not lining up right you are probably doing something wrong.


This is what has me concerned. I have followed the directions to a "T". The lower skin is drilled and cleco'ed in place, and the upper skin is just clamped on. It cleco'ed to the aft spar and lined up with all of the rib holes perfectly, except for this one errant hole.

Maybe I'll re-square the wing and look again? I keep thinking I must have something on backwards, or maybe the right and left skins are different?