Counterbalance skin trick

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captain_john
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Counterbalance skin trick

Post by captain_john »

This is brilliant!

Image

Kevin is a local builder here on Cape Cod. I am getting ready to rivet together my right elevator and was noodling over a way to use solid rivets in lieu of pop. I pinged Kevin's site ( http://www.gis.net/%7Erosette/061003.html ) and POW!! There was my answer!

Good trick, Kev!

I am doing the same!

8) CJ

P.S. I got a question. Why does everyone (inluding the plans) say to edge roll your leading edges before final riveting?

I don't understand what will happen if you don't?
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Post by Spike »

I believe it is to make them sit flatter than they would otherwise. Let me dig up a picture of the leading edge of my training project which I did not roll the edges and you will see what I think they might be trying to mitigate.

-- John
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Post by Spike »

John, heres a picture of my training kit. Notice how the skin bulges a bit inbetween rivets. I think they are suggesting that you roll the edge to keep try and reduce how much of the skin is protruding.

-- John

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728GD
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Post by 728GD »

Your right on target. By rolling the edges prior to the final riveting the edges will not "bend up" when you press your rivets and you will end up with a nice flat surface. You don't need to bend the edge much, if you see a line where you "edged" it, that is more than you need. Play around with some scrap and you get the hang of it quickly.
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Post by captain_john »

Yah... well I unnerstan' ya need to do it, as I did on my rudder:

Image

The way it sounded to me was that it should be rolled prior to riveting the spar into place. That is what blew my mind.

I guess it is just how I read it that it didn't make sense.

I have it all laid out and ready to drill now! Check it out!

Image

Image

I will let you know how Kevin's little trick works out!

Stay tuned!

:popcorn: CJ
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Post by captain_john »

Well, It worked out REALLY nice!

Image

...and a closer look:

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It turns out that this really isn't much of a trick at all. I looked at my buddy's -8 plans and it is spelled out on his set. I would guess this change is on all the 2002 and newer sets.

Nevertheless... it is better than the "pops"!

:wink: CJ
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Post by Snap »

Mate, that is some really nice work. How long did it take you to get your head nice and flush like that. There doesn't seem to be any gap at all around them. Nice, Very Nice!
:yay: :yay: :yay: :yay: :yay: :yay:

Can't wait to see how they fill up when you paint. There shouldn't be any sign of them at all.
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Post by captain_john »

Great question, the trick to "flushness" was passed onto me by a fellow builder. What you do is just "kiss" the dimpled hole with the deburring tool prior to riveting. It is as simple as that. Give it a try!

8) CJ
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Post by Ron »

Another great little trick is to chamfer the edge of the skins at this transition. Smooth's it out nicely! :wink:
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captain_john
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Post by captain_john »

Hmmmm, what U mean?

Mebbe I will do it on my left one.

File the leading edge of the counterbalance skin edge?

Is that what you mean?

:?: CJ
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Post by Ron »

hey John,
on the counterbalance skin which fits under top skin you would chamfer that square end and the inboard side as far up as would flush up with top skin. then on top skin where it meets couterbalance skin can be chamfer to smooth out transition. This can all be acomplished with the scotch bright wheel. As soon as i get the pic's back i can post, good luck!
Ron
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Post by Guest »

Ron has a grand idea about the chamfer. I did it to my counter balance skin as well and it looks pretty good. It's also good practice for when you skin the wings. There's a couple places where you'll need to do that. Someone also mentioned practicing with the edge roller on some scrap before you try it for real. I would take that advice to heart. Those nifty little edge rollers the tool guys love to sell us can absolutely destroy a good piece of skin if used with too much gusto. And too much aint that much. The skin stretches and if it goes to far..... Shipping costs for replacement parts from Vans is pretty spooky. Don't ask me how I know.
Nice looking work so far, Capt. J - I'd fly it. Richard

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captain_john
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Post by captain_john »

Thanks!

BTW, an improvement to the Cleaveland edge roller I think... finer threads on the vise grip adjustment part.

...and roll the wheels with your fingers for more directional control!

Yes, this is all training for the wing skins!

:) CJ
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It's all over but the flying! 800+ hours in only 3 years!

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