> I machined a cone in a dowl that is a light press fit in the center hole
of
> the prop.  I then ballance the prop on a pointed rod (held vertical in a
> vise) in the center of the machined cone.
>
> A sensitive round bubble level (like those on a transit) indicates the
> direction and amount of imballance.  I use weights rivited to the spinner
> backing plate to ballance the whole assembly.
>
> Tracy

So does the flat surface of the cone get pressed in past the surface of the
prop so that the point of contact is inside the hole to give some stability?
Thanks for clarifying this
Peter