Instead of drawing the thread, which I never did when using a pencil and T square for engineering drawings back in the day - well before CAD was even a thing. Decide what your outer shaft diameter needs to be then tell the machine shop you want, for example an ISO thread form, with the standard pitch - assuming you are in a metricated country of course. No need to design it or render it at any point,  their machining center will handle everything for you, they probably have a 60 degree threading tool loaded all the time in the tooling station. Just be sure to pick a standard pitch and diameter from the ISO thread tables then all the hard work is done. Tried to learn FreeCAD from the tutorial videos, hated it, although I'm sure with time I might appreciate some of its features. Roger.