Thanks Mat for your reply,

it flutters at low and high speed, I dont have to use the Ailerons to make it flutter.
When it happens and drops the wing I can correct it by applying a left stick to level out and increase the speed and it will come back.

i can roll the plane and there is no sign of it.

The RH controll rod had a slight curve in it but swapped it to the LHS made no diff.

I dont understand how to balance the surface. Is the rod running length ways (horizontal) or through the top and botttom (vertical 45deg) I can understand the vertical one as used in full scale.

To make the rods shorter I can fit another servo if you think the harmonics is making the rods flutter.

Thanks Jim West Aust.