Stiffness Issues
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_deltaV
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Stiffness Issues
I'm in my second year doing wright stuff and have already run into an old problem from last year. I've run out of stiff balsa and am only left with the light flexible A grain balsa. When I go to fly, the wings bend upwards and warp to a point of crashing. Has anybody had this same problem, and if so, how did you fix it? Currently trying carbon thread dipped in glue to stiffen the wings.
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DoctaDave
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Re: Stiffness Issues
You can try doubling the spars so they are thicker. I usually don't have this issue, since I always use very dense and beefy spars. They take the largest beating so it's worth investing the weight.
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jander14indoor
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Re: Stiffness Issues
What density balsa are you using for spars? What dimensions?
With the generous weight allowances under these rules it shouldn't be too hard to select spars that are plenty stiff without finding the really rare stuff.
If you want to use something to stiffen the balsa, your carbon fibers should work, but you don't want to use much. A VERY little will do a lot. You'll need to apply it top and bottom. To figure out how to do it will little weight gain, look around on the web for how F1D fliers attach boron fibers to their spars. DON'T use boron, substitute the carbon instead.
Uou may want to document your build process with pictures in case an observant ES notes the reinforcement. That way you can show you did NOT use boron (the one forbidden material in WS).
Note, if you apply the carbon top and bottom it doesn't need to be stiff before applied to work, just apply a little tension so there is no slack when glued.
Jeff Anderson
Livonia, MI
With the generous weight allowances under these rules it shouldn't be too hard to select spars that are plenty stiff without finding the really rare stuff.
If you want to use something to stiffen the balsa, your carbon fibers should work, but you don't want to use much. A VERY little will do a lot. You'll need to apply it top and bottom. To figure out how to do it will little weight gain, look around on the web for how F1D fliers attach boron fibers to their spars. DON'T use boron, substitute the carbon instead.
Uou may want to document your build process with pictures in case an observant ES notes the reinforcement. That way you can show you did NOT use boron (the one forbidden material in WS).
Note, if you apply the carbon top and bottom it doesn't need to be stiff before applied to work, just apply a little tension so there is no slack when glued.
Jeff Anderson
Livonia, MI