Wing wash on B Buckle Super scorpion

[911hillclimber]

Hello all, I hope you can help me. I built the airframe of the Super Scorpion about 20 years ago and never covered it. It went in the loft, unprotected.

I dug it out over Xmas and have noted a wash-in or warp (!) of the wing evenly on both sides of about 10mm. The warp is one of the trailing edge rising upwards toward the tip from about 1/3 the 1/2 span of the wing starting from the root.

Is the wing useable?

Rest of the model is sound remarkably.

I plan to cover the frame in silk and dope, it will be electric.

Thabnks in advance, Graham.

[Pete Collins]

Firstly, if the trailing edge rises toward the tip that's washout. Leading edge rising ,or trailing edge falling would be washin. Washin would be a definite no go but a bit of washout is no problem provided that it's equal on both wings. If not then you're going to have to get it out. To do that hold the wing in a stream of steam from a kettle (Don't burn yourself!) and when it's good and damp. pin the wing down flat on a board and leave it to dry for a few days. With a bad warp you sometimes need to pack the wing a little to twist it the opposite way so that it springs back to straight when released. With a warp that's been there a long time you may need to try couple of times before you succeed. Also, with silk and dope covering you can sometimes pull a twist either in or out during the covering stage but you're better to try to loose the warp before covering if you can.

[John Wagg]

" The warp is one of the trailing edge rising upwards toward the tip from about 1/3 the 1/2 span of the wing starting from the root. "

That sounds fine and possibly was how it was meant to be built in the first place. Especially if both wings have the same equal washout. Done this on a few planes overtime.

Helps with countering "tip stalling" Try to keep both wings the same when covering.

[Braddock, VC]

There is built in washout in the SS wings IIRC the trailing edge has to be carved to include it.TBH I built mine in 2007 so it was some time ago.

If I were you I would be more concerned about the glued joints after 20 years in the loft, if you used ca then it should be ok whereas some of the pva glues may be suspect.

[911hillclimber]

Thank you all.

I looked at the plans again and the is a built in wash! Clean forgot about that.

there are a few dry joints to replace, used balsa cement everywhere at the time.

Thinking the worst, I had a BB Standard Buccaneer for Xmas, so will do thar first.

love the looks of the Scorpion, so would be nice to finish it.

thanks again.

Graham.