Pfff... I got my Tundra back from sitting in a tree for ten days! Storms, rain, sunshine, and more rain, ... we've seen it all in those days. Now it was time to make a plan for repairs. What needed to be done, and what materials would I need to get her up and flying again...
First of all, the battery had died, obviously, from being connected all the time. A LiPo battery that is discharged that deep, won't be easily brought back to life. And if that should ever work, then it is still questionnable if the remaining capacity is worth keeping the battery.
Putting in another battery (after removing the propeller!) revealed that the ESC and motor were still fully functional. Same for the servos that move the ailerons, horizontal stabilizer, and rudder. Unfortunately, the flaps switch did not move anything; those servos were completely unresponsive.
The rudder, including the plastic piece that holds the rear wheel, was completely separated from the fuselage.
In the right-hand horizontal stabilizer, there is a carbon fiber spar at an angle of about 45° with the longitudinal axis. The outward portion of that stabilizer had broken off along the spar.
The "finder" had removed the main landing gear to make it more transportable. Not by removing the screws, but by detaching the plastic base from the fuselage.
And, of course, there are the dents and bruises from hitting the tree, hitting the plane with tennis balls, and from falling down from the tree when finally rescued. This also bent the wing spars, which at first seemed fixable, but in practice proved rather difficult.
Putting it all back together was reasonably straight-forward, except for the flaps-servos. One would think 9g micro servos are 9g micro servos, but no, the ones I got had a housing that was about 1mm larger. Also, the spacing of the holes in the horn was different, and the holes were too small to put the control rod through. The teething was different too, so I could not re-use the old Horns. So, after determining which hole to use, drilling it out to a large enough diameter, and enlarging the cavity in the wings, glueing the servos in the enlarged cavity, all that remained was shortening the servo leads so they would fit in the green adapter plates that serve as contacts between the wings and the fuselage.
For setting up both servos, I bought a servo tester, so I could place them in the middle position, which would be the flaps 1 position of the three-position switch used to operate them. All in all, it ended up pretty decent, but there was still a bit of difference in flap extension between the left and right flaps, so there might be some roll effect from deploying the flaps. If so, I might need to create another mix between flaps and ailerons, just like I already did for flaps and elevators. But we'll have to see, once we get airborne again.
Now, it's off to the camping, and hoping for good smooth weather for a renewed maiden flight. See if she still flies. And if so, if she flies straight...
First of all, the battery had died, obviously, from being connected all the time. A LiPo battery that is discharged that deep, won't be easily brought back to life. And if that should ever work, then it is still questionnable if the remaining capacity is worth keeping the battery.
Putting in another battery (after removing the propeller!) revealed that the ESC and motor were still fully functional. Same for the servos that move the ailerons, horizontal stabilizer, and rudder. Unfortunately, the flaps switch did not move anything; those servos were completely unresponsive.
The rudder, including the plastic piece that holds the rear wheel, was completely separated from the fuselage.
In the right-hand horizontal stabilizer, there is a carbon fiber spar at an angle of about 45° with the longitudinal axis. The outward portion of that stabilizer had broken off along the spar.
The "finder" had removed the main landing gear to make it more transportable. Not by removing the screws, but by detaching the plastic base from the fuselage.
And, of course, there are the dents and bruises from hitting the tree, hitting the plane with tennis balls, and from falling down from the tree when finally rescued. This also bent the wing spars, which at first seemed fixable, but in practice proved rather difficult.
All in all, the damage seemed repairable, and nothing, except one tensioning spring of the main landing gear, was missing. Upon investigation of the flaps servos, they just wouldn't budge, Not when powered electrically, but also not when moved by hand. So they were mechanically stuck somehow.
I ordered a main gear set (the metal bent pieces, plus the springs), some plastic pin hinges to replace the foam hinge of the rudder, two servos to replace the flaps servos, and a wing spar set. I figured that the rest should be doable with some foam-friendly glue, and some reinfocement tape here and there. Both of which I had already laying around.
Putting it all back together was reasonably straight-forward, except for the flaps-servos. One would think 9g micro servos are 9g micro servos, but no, the ones I got had a housing that was about 1mm larger. Also, the spacing of the holes in the horn was different, and the holes were too small to put the control rod through. The teething was different too, so I could not re-use the old Horns. So, after determining which hole to use, drilling it out to a large enough diameter, and enlarging the cavity in the wings, glueing the servos in the enlarged cavity, all that remained was shortening the servo leads so they would fit in the green adapter plates that serve as contacts between the wings and the fuselage.
For setting up both servos, I bought a servo tester, so I could place them in the middle position, which would be the flaps 1 position of the three-position switch used to operate them. All in all, it ended up pretty decent, but there was still a bit of difference in flap extension between the left and right flaps, so there might be some roll effect from deploying the flaps. If so, I might need to create another mix between flaps and ailerons, just like I already did for flaps and elevators. But we'll have to see, once we get airborne again.
I used glue and tape to put it all back together again. Yes, it's ugly duct-tape, but then again: that's strong with good adhesion, yet still flexible enough to serve as hinge strengthener. And I don't expect this plane to gain beauty with experience; I expect to crash a couple of times more, before I really get the hang of flying model planes!
Exception is the rudder hinge; I put thee pin-hinges instead of that one. That worked out great! It was a little bit of a process to get all parts aligned well, including the pins of the hinges (they all three need to be in line, or you'll get weird forces, and bends). But that turned out pretty pretty, I think!
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