This is NOT necessary. It is actually a waste of time.
but remember to balance the center of gravity,the blades have to be the same center of gravity
A simple see-saw balance is all that's needed.
This thread has more detail,
On page 4 we find,
All rotor blades are designed with adjustable weight packages so that all blades can be shipped from the factory with the exact same span moment.
Notice that says moment, not weight or CG.
Junmping down to the "conclusions" we find,
The United States Army now employs dozens of Universal Static Balance Fixtures within all levels of maintenance, depot, intermediate and unit. The United States Army has saved millions of dollars in reduced rotor blade returns to the manufacturers and depot repair facilities. The United States Army has saved millions of dollars in reduced maintenance test flight expenses by cutting associated activity in half.
It looks like they like static balance also, when done right.
This article from the same source says it better,
If it's good enough for the full size, it's good enough for models.