Steaming sheeted wings

[thepilotbruss]

I was given Wind Dancer that needs a little help. It's 134 in. balsa over foam core wing and one of the wings has a warp in it. I can probably get it out when I apply new covering but I would like to try and steam it out. This is where you nice people come in handy as I have never used the steaming technique. Do I steam the concave(SP) side or the convex side? Is a tea kettle going to produce unough steam for this size of wing? After I steam it do put the wing on a flat suface with weight on top of it to hold it flat or will I need to actually bend it slightly further in the oposite direction of the warp? And lastly, what is the best method for removing old covering off a sheeted wing.

Thanks for all your help, Justin

[Ollie]

I don't have experience with steaming a warp out of this type wing.

I would soak both top and bottom skins with unscented household ammonia and over twist the warp out. You have to allow for a little spring back. You have to hold the reverse twist until all the ammonia evaporates. This calls for some kind of a jig to hold the warp out for several hours. Fortunately the process can be repeated if you don't get it right the first time. Be careful that you don't distort the airfoil with the holding jig! Trace the root airfoil onto a piece of plywood and cut out the airfoil shape so that the plywood rectangle fits snugly over the root of the wing. Use another piece of plywood and fit it snuggly around the wing tip similar to the root ply piece. Remove wedge shaped pieces from the bottom edge of the plywood so that when the bottom of each piece of plywood is forced onto a flat surface the desired twist (allowing for some spring back) is held in the wing. This kind of jig will prevent distorting the airfoil and give access to both the top and bottom of the wing for applying ammonia. This is messy and smelly and best done outdoors. It works and is a more or less permanent cure.

[thepilotbruss]

Thanks for the advice. The wing and tail are now covered and looking good. Chances are I will be able to fly it this weekend. Has anybody here flown a windsong? I'm wondering if this glider has some bad habits I should be aware of before the first flight.

Thanks, Justin