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Archive for December, 2016
Posted by springer | Dec 09, 2016 @ 06:15 PM | 35,343 Views
I have been seeing guys do some astounding stuff with MPF (and Readiboard at FliteFest!) in larger size planes, so figured it was time to try one myself. In the best scratchbuilder tradition, I started with two sheets of MPF and cut diagonals that gave me what should have been an 8 foot wing. However I incorrectly set the angle of the tips (not parallel to the centerline) and once I sorted that our had a 7 ft span. I TLARed a symmetrical airfoil and did offsets to get the ribs in a constant taper across the half span. Decided to do something different from my usual solid wood spar and build up one. Used Quarter inch square section Pine, poplar or bass ( don't remember which) for top and bottom, tying the ribs to them at "appropriate locations". Then in a fit of creative passion, I decided to make shear walls for the spar out of some cardboard from packing of something. It is like a tablet back, about 1/16" thick. Glued pieces to each side of spar with gorilla glue. This made an amazingly stiff spar, and Probably makes the plane. Wrapped the MPF over the ribs as a skin, and cut out the pocket for motor/prop. Made pocket for battery in nose, Added a leading edge spar and shaped to the airfoil LE. It came together amazingly well, considering no plans of any type. Of course doing a simple wing helps! Build thread here: https://www.rcgroups.com/forums/show...g-MPF-and-wood
7FW android (1 min 43 sec)