I received the metal gear servos. These are more accurate, cheaper too.
There was still some wobble left.
Tried loading with some weight first, that reduced the wobble
So I removed the counter weight altogether, and that causes a preload.
These new servos cannot be moved by the weight of the unbalanced yagi, Servo current that way stays at 70 mA with occasionally a few hundred mA.
That part of the project is now a go.