bevel upper wing skin at overlap?

prkaye · #1 03-31-2007, 11:58 AM

For the upper wings sink, the outboard skin overlaps the inboard skin along its entire width. Should I bevel the inboard skin along this edge so as to reduce the "step" from one skin to another. I know the plans say to bevel the lower skin in one corner where they overlap, but I don't see anything about beveling the top skins...

AX-O · #2 03-31-2007, 12:38 PM

My Buddy and I did this last weekend. We just did the inboard skin. Turned out awesome! Better than a quickbuilt wing that I compared it to. My advice is to take your time, you don't want to remove too much alum from the skin. It will make the edge of the inboard skin weaker.

prkaye · #3 03-31-2007, 12:44 PM

Thanks Axel. So I guess this has to be done prior to dimpling? Just using a file?

G-force · #4 03-31-2007, 04:13 PM

One of the drawings has two detail drawings about the overlap, one from each angle (for/aft and left/right). IIRC, we (me and Axel) beveled only the inboard skin (thats the one underneith, right?) along the side and forward edge. This allowed the overlapping skin to pull in tight along the tank and also not have a bump side to side. We used a right angle die grinder with a 2" dia sanding disc to rough it out then a medium scotchbrited disc to clean it up. The bevel tapered over a distance of about 3/4" of an inch from the full thickness of the material to about 1/4 of its thickness on the edge. We also beveled the lower, outboard edge of the wing walk doubler to smooth that transition as well.

Brantel · #5 03-31-2007, 05:17 PM

I cut a notch at the overlap on the inboard skin that is similar to the notch on the trailing edge side where the two join at the training edge. I cut this notch to about 1/4" before the first rivet holes.

The outer layer will nest down in the notch and be flat at the tank junction.

This creates a nice and tight sloping transition with absolutly no step off of the tank and a gradual transition up the ramp to the area were the two skins overlap.

I did this following the advice of my CFII and how he did his.

This took about 5 minutes to cut, file and smooth.

Looks great.

AX-O · #6 03-31-2007, 09:11 PM

Quote:

Originally Posted by Brantel

I cut a notch at the overlap on the inboard skin that is similar to the notch on the trailing edge side where the two join at the training edge.

Did you use proseal or something to seal the small gap between the inboard and outboard skins? Seems like water would leak in. The gap at the rear of the wing is aft of the rear spar so water could potentially leak from top to bottom however, water would not leak into the wing.

AX-O · #7 03-31-2007, 09:16 PM

Quote:

Originally Posted by G-force

One of the drawings has two detail drawings about the overlap, one from each angle (for/aft and left/right).

Drawing 17A section D-D and E-E.

Quote:

Originally Posted by G-force

IIRC, we (me and Axel) beveled only the inboard skin (thats the one underneith, right?).......

Yes.

Brantel · #8 04-01-2007, 09:19 AM

Quote:

Originally Posted by AX-O

Did you use proseal or something to seal the small gap between the inboard and outboard skins? Seems like water would leak in. The gap at the rear of the wing is aft of the rear spar so water could potentially leak from top to bottom however, water would not leak into the wing.

Plenty of places for water to enter the wing, this one is very small when done properly.

It is no different that the area where the tank skin and the leading edge skin meet near the front spar.