yeap land the model after a flutter, that's how i lost one of my models. I slowed down but the fluttering bent one of the
control rods. I jammed the sticks but it wasn't enough to prevent the model from rolling.
Come to think if it...it was the right airleron.

But if there's too much of a gap from not properly mounting CA hinges, this will enhance the fluttering.
Yeap the control horns from kits or Arf arn't exaclty precision...there's play in them.

I also had a great discussion about the rear of the control surfaces. Some people say to round them.
I wasn't really sure..but I remember doing reserch on this matter. I read that you should leave them square.
Untappered control surfaces such as the airleron of a 4*

Yeah..you can hit natrual harmonics at the 12 fret or the 5th fret of the guitar. Some guitar neck are actaully not flat.
It's bowed and the lowest piont is between 5th and 7th fret becuase that's where the string vibrate back and forth the most.
It also depends on how the angle of neck is mounted to the guitar body.

Kind of like not all model's wings are flat...they'll either have wash in or wash out.

It's pretty neat to get into hobbies and learn the variouse details.