Sunday, December 31, 2006

Discus complete, madiened!

It flew! Finally completed the discus n brought it to the slope. Was abit scare, hesistant with the fuzzy feeling, dont know if she's going to fly... The winds were changing directions on and off, maybe i should wait for another better day, nah couldn't wait, i had to do it. Took out the elster for first flight to get a feel and mentally prepare myself. The launch, turns, approaches for landings were rehearsed. Did a range check , ok, control surfaces check, ok.

Thats was it all ready to go. I could feel my adrenaline pumping as i held the plane at the edge of the slope ready for launch. All eyes were on this one as i passed the plane to WY for the first launch. 3,2,1 go. Off she went. She was diving quite fast I had to hold lots of up elevator to keep her up.First few rounds were tensed as I was not used to size and speed.Had to bring her down for landing as she was at too low attitude. The first landing was quite hot and she skidded on touch down. Phew sense of relieve as i went to pick up the plane. CG was too forward, move the battery pack back,wait for my heartbeat to settle down for another go. This time self launched it and she flew beautifully. The handling was crisp, solid and she had good energy retention. 2nd landing was better managed. Will spend the next few flights trimming her out more.

Some of the finishing build pics. Made plug-n-fly wings so that the wings servos are auto connected when i slot the wings in. Did this by first using transparency plastic sheet as template to mark out the position of the deans 3pin connector. Use the 2 incident pins as guide. Flip it to the other side n mark out the same position on the fuselage area. Slowly dremelled out the hole to fit.Made my own twisted extension wire (suppose to reduce interference) by first splitting them into individual strands, then slot into the dremel tool, hold the other ends together n spin. Soldered extension wire to the wing servos, slot through the hole n solder to deans connector. Slot in and glue with slow-cure CA. Did this for fuselage side as well. Turned out pretty fitting. metal crevis for the controls. Then cut servo covers to size.

Fuselage. The elevator was connected using a ball link with stud type. TT raptor ball link connectors with TT heli rods connects to the elevator servo. No slop at all! Epoxied the servo the some balsa pieces so that it can grip on both insides of the vertical stab.Epoxy it in. The rudder piece was the most time consuming part. Had to measure many times the position of the ball link placement to ensure no binding.The rudder is hollow as well so drilled out a larger hole, filled it up with epoxy and microballon mix so the that ball link has some where to stick to. Rudder pushrod used was a 4mm carbon tube. The rudder control outlet was slanted so the servo had to be placed on starboard side to ensure no binding. Servo tray reworked. Finally glue in the rudder stab.

Final steps. Made the battery pack. Measured the incidence of the wings and stabilizer stab. Made weights with fishing sinkers to get the correct C.G. Finally polish the wings , fuselage with some car wax.

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