Moment of Inertia is denoted by I and is the angular analogue of mass. It is defined as the sum of (mass of molecule x distance to pivot squared). This is approximated by an integral (calculus), which is easier to calculate.
Thus, for a beam of just sufficient length and just sufficient strength to support the counterweight, the greatest Moment of Inertia I will be obtained by positioning the beam extending from the pivot parallel to an extension of the arm wand.
The obvious tradeoff is the amount of material required to position the beam that way.
There are other tradeoffs - one wants adjustability and rigidity and resonance control in the beam. Thus a system of a light but rigid tubing (say magnesium), with a lump of tungsten on the end, threading into a nut on the end of the arm, would give you the highest I/m ratio, but may be compromised with respect to resonance. I should try that on the Trans-Fi.
Thus, for a beam of just sufficient length and just sufficient strength to support the counterweight, the greatest Moment of Inertia I will be obtained by positioning the beam extending from the pivot parallel to an extension of the arm wand.
The obvious tradeoff is the amount of material required to position the beam that way.
There are other tradeoffs - one wants adjustability and rigidity and resonance control in the beam. Thus a system of a light but rigid tubing (say magnesium), with a lump of tungsten on the end, threading into a nut on the end of the arm, would give you the highest I/m ratio, but may be compromised with respect to resonance. I should try that on the Trans-Fi.