Warped rudder

[Coloradoken]

Any good ideas on taking out a warp in a rudder? Was OK with frame tissued but after water spraying the @#?%$/ thing looks like a pringle. Guess the weave of the paper was not the same in all directions but what can I do now?

[PsyberPhlier]

First, don't shrink with water. I just learned about shrinking with alcohol to reduce the wet time and speed up dry time. It really works.

To take the twist out, you can try re wetting and pinning it into a straight position until it dries. I often pin or magnet things down to my building board until they dry. Make sure there are some thin stringers under the part to allow air to circulate.

Ted

[Mitch]

Yes, you can do that... and even after tails are doped it may develop a twist. Boil some water in a pot or tea kettle and get the tail into the steam. It will soften and then twist the tail the other way... I need to do this with my SE5 (100 series). It was fine for a while but a warp developed...

[David Lewis]

If you shrink tissue with water, the trick is spraying a very fine mist and using as little water as possible. Just barely damp. This results in fewer wrinkles, besides minimizing the chance of warps. The tension in the tissue distributes more evenly. It may be helpful to overbend the surface in the opposite direction of the warp and then let it dry.

When it comes to preventing warps at the lowest possible weight, thickness is your friend. For example, if the tail surface is 1/8" thick instead of 3/32", you can make the parts narrower, use lighter balsa, and come out stiffer, stronger and lighter at the same time.

[Coloradoken]

Thanks for the info. I'll give them a try.

[Coloradoken]

It worked, folks. Many thanks