construction error: VERY BIG

[LeoB]

I am building a 1/4 scale Inland Sport(1930 age parasol type) model, about 80% done. When setting up the wings for alighnment i dicovered that i had a very bad error; i had somehow put in 2 degrees WASHIN instead of WASHOUT. The base root dihedral is +2 degrees with tips of +4. MUST CORRECT.

As the wing is made up of scale type ribs,sheeted leading edge, capped and all i hate to reconstruct!

Is there any way anyone knows to warp the conpleted wing enough to correct this problem?

Any and/or all help appreciated!

[Gerryy]

Depending on the general stiffness of the wing structure, you could first cover the model but not shrink it tight. you may be able to rig the wing in place with the wing struts since it is a parasol design, then when you get the wing structure in the right twist, shrink the covering. It might hold the twist you need. 4 degrees is a lot to take out, maybe just take away 2 degrees so the wing is straight and then rig your ailerons to get the two degree of washout. 'good luck
GY

[PipesCS]

I have a friend who purchased an ARF (will not mention manufacture) and after it crashed (went into a spin anytime you turned left) we found the wing wingpanel was seriously warped causing wash in as you discribed. Tried Gerrys method but it was too much.

We finally stripped the covering an pried up the leading edge sheathing. After pinning the frame down straight it was a simple matter to redo the wing sheathing. It was enough to hold it straight.

[Mode One]

I have a friend who purchased an ARF (will not mention manufacture) and after it crashed (went into a spin anytime you turned left) we found the wing wingpanel was seriously warped causing wash in as you discribed. Tried Gerrys method but it was too much.

We finally stripped the covering an pried up the leading edge sheathing. After pinning the frame down straight it was a simple matter to redo the wing sheathing. It was enough to hold it straight.

O.K.; but, try the first suggestion before any major surgery if the wing is already covered! If not, by hand, can the wing be twisted 4 degrees, and how much force does it take to get the proper wash-out into the wing? If it's difficult, it's unlikly the coving material will provide enough force to change the twist and you will need to resort to PipesCS suggestion.

Good luck!

[edmoor]

set up the wing where you want it to be....ie....clamp it....weight it....etc. use steam.......let it dry.......it will stay.

[Triple Nickle]

Yes,,,Steam is by far the best suggestion. The only obsticle standing in your way is to build a steam box large enough for the wing, and a way of injecting steam into the box. Build the steam box with a hinged top so that you can easily remove the wing once it's soft enough for bending into the desired shape. Best of luck,,,