Coroplast and Deltas
Just thought I would let you guys know that I flew my Delta using coroplast for control surfaces. I took some left over 4mm coroplast sign board and used it for the ailerons, elevators and my vertical fin/rudder.
I routed out a slot in the trailing edge less than an inch deep with my dremel. Squirted in a little Pro Bond poly glue the whole length and then shoved in the coroplast. The coroplast fit perfect in the 1/8" trough esecially when the glue foamed up. The surfaces were about two inches wide plus what ever was shoved up in the trough. The coroplast was then split on one side of the flute to make the hinge. I then took small strips of 3/32" balsa and pushed them in the flutes a couple of inches to stiffen up the coroplast for the control horns.
I split my trailing edge into three equal lengths, elevator in the middle and ailerons on each side. Each was powered by a single standard servo. Needless to say with the first flight it buried the nose. I had no mixing of the ailerons and elevators and when it slowed, I didn't have enough elevator to hold the nose up. At cruising speed I had plenty of elevator though. I have since mixed in about 30% aileron with the elevator and it is plenty of control.
For the vertical fin, I used the dremel to dig a trough in the top of the foam about an inch and a half deep. I took a rectangle piece of coroplast and folded over one corner to make the fin (making the leading edge 45 degree angle). Basically so that if you looked at one side the flutes were vertical, the other side the flutes ran horizontal, with the glue in the middle it was extremely stiff. When I folded it, the vertical flutes stuck below the bottom of the fin about an inch and a half to stick in the trough in the foam. The vertical flutes also stuck out the back of the fin about two inches to make the rudder. I split a flute to make the hinge same way as the aileron/elevators.
It made for an extremely fast build and flies great. Just thought I would throw that out for another idea for this plane...
-Scott-