[InFlight]

The maximum torque capability for a 0.5" hex shaft is = 0.0262 * Yield Strength.

A 6061-T6 shaft can theoretically take 1048 in*lbs (or 87 ft*lbs)
7075-T6 shaft is likewise is 1912 in*lbs (or 159 ft*lbs)

You would be far more likely to break some FRC gearbox teeth before you ever failed these shafts in torsion.

As someone who has ran machines in an ME stress lab, you'd be shocked how many rotations a two foot bar stock can make before it ultimately fails! (Tinius Olsen Machine)