Torque tube inner shaft kit

[rotorwrench]

I'm not sure if Dick made those himself or if he contracted them out to a machine shop. The shaft can be cut out on a lathe and the splines can be cut on a horizontal mill with the aid of a rotating indexable tool holding device. If further hardening of the finished shaft is needed, it can be done by any number of companies that specialize in heat treatment processes. The rear piece can be made from a 10-spline to 6-spline adapter. A thick wall chrome moly tube will work but there are other seamless thick wall tube types that might work just as well. It just needs to be able to withstand the applied torque of a healthy flathead.

It is difficult to find the old tube type drive shafts in good condition these days.