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PostPosted: Wed Nov 01, 2006 6:16 pm
by LAZAIR 4 EVER
This is my fixed left wing with the two sticks and they ligne up.realy good

PostPosted: Wed Nov 01, 2006 6:18 pm
by Shannon
I took the liberty of rotating your picture so the twist would be more evident. Definitely out of wack.

PostPosted: Wed Nov 01, 2006 6:18 pm
by LAZAIR 4 EVER
This is an other view of the bend down leading edge on the left wing.
Befor geting fixed.
You can see that the foam rib got compressed and deformed.

PostPosted: Wed Nov 01, 2006 6:27 pm
by LAZAIR 4 EVER
I also wanted to show to who may be interested, the inside of a outbord leading edge as someone was asking for pictures earlier on the forum.

PostPosted: Wed Nov 01, 2006 6:33 pm
by LAZAIR 4 EVER
Another one!

PostPosted: Wed Nov 01, 2006 8:14 pm
by Shannon
Though I can't say for sure it looks like you have a relatively minor problem. I don't know exactly how I'd go about fixing this but I don't think it would involve making a new outboard skin section.

One thing of interest is the bead of adhesive run down the nose of the D-cell skin. Someone told me that wings had ribs glued like this but I had never seen it myself. Typically you would find that each rib had glue applied around the entire perimeter.

Being you have gone this far into the wing it would be a great time to open up the rest of the D-cell and re-glue all the ribs.

Shannon

PostPosted: Wed Nov 01, 2006 10:36 pm
by flyalaz
LAZAIR 4 EVER @ Nov 1 2006, 06:18 PM wrote: This is an other view of the bend down leading edge on the left wing.
Befor geting fixed.
You can see that the foam rib got compressed and deformed.


Looking at your end-on pictures, it appears that the D nose foam ribs have been mislocated too far towards the bottom. The original assembler of the wing would have had to bend the spar backwards at the top to get the skin on, causing that twist. The metal rib bracket looks like it's in the right place, but the rib itself is too low. It might be a progressive thing that started a rib or three more inboard, and became excessive at the last rib. If the ribs are removed, maybe it's possible to relocate them after getting rid of the twist in the spar. The mislocation will obviously be more pronounced at the outboard end, causing double holes. If the mislocation doesn't cause the aft row of rivets to foul in the radius of the spar flange, perhaps a doubler can be nested inside of it, and the original skin rivet holes re-drilled.

just a thought,
Karl

PostPosted: Thu Nov 02, 2006 7:37 am
by LAZAIR 4 EVER
Shannon! You're right about the glue. and I may just do what you said about openning the whole leading edge to check the ribs.
My problem is minor I know but it has to do with re bending the leading edge and that's what I am a little suspicious about.

Hi Carl! You see the way it looks it could have been what you just said but it realy is the leading bend that is misslocated on the tip of the leading edge and on the tip only .In other words, if it is not bent at the right place. one lenght of skin runing from the spare to the leading edge will be too short (in my case the bottom one) while the other will be too long(the top one). This twists the leading edge down and twist the end of the spare.
Buy the way My spare is only twisted when the leading edge is instaled on it. once the sheat of leading edge is off, the spare comes right back to a staight and square position with the rest of its lenght so are the ribs.
All I need is to re locate the bend at the tip. The inbord portion is good. but how do you shifft a bend on a leading edge only at one end?
That's the question!
That's why I want to get to know how they formed this part of leading edge at the factory.
BTW Carl! I have somme free time on my hands for the coming month. We should get together and talke LAZAIR one of these days. I'll call you.

Thank you guys for your support!

LAZAIR 4 EVER

PostPosted: Thu Nov 02, 2006 7:54 am
by russell
Shannon, not that it's any help to Lazair 4 Ever's plight, but just for discussions sake I thouhgt I'd just jump in and say that none of the foam ribs in the wings of my Lazair have glue on them any where except on the spar.

As I stated earlier, I have to fashion that piece of skin also. My vision is to duplicate the foam ribs from 1x's and firmly attach them at the proper spacing along a mock spar also made of wood. this would make a good form for checking the shape of the piece but would not be of any use in bending it I feel. Still thinking on that.

Russell

PostPosted: Thu Nov 02, 2006 9:33 am
by flyalaz
How to shift one end of the skin: B.F. and I.= Brute Force and Ignorance


Russell has a good idea with the leading edge mock-up. Once you have the correct jig built and the skin in it's proper place all along the spar bottom, (or possibly the top), forming the skin with brute force (to be indelicate) various mallets, straps, and/or a shot bag and wooden rib forms should work, but will take time to do a nice job. The hardest thing to avoid is making an "oil can" effect while you are doing it.
The thing is that the skin would need to be reworked along most of it's length, and not just locally around the problem, otherwise a kink or ripple will be formed. An easy way to visualize this is to take a sheet of paper and form it into the D nose shape that you have now, and push just the end of it to the new form. You'll see how the paper deforms. (This will also give you an idea of how the metal sheet needs to move.) Now, fix just the bottom in place, and form it the way it needs to move. Try the same thing with just the top in place. One way may be easier than the other to form.

Just some ideas.
Karl