Yep, I'm more of a writer than a machinist.

I'm going to read your post a few times to try to figure out what your part looks like. I would love to see a drawing or picture. I'm going to try to understand without the drawing or picture ... bear with me.

In any event, you can see what I am trying to do. My current plan is to use the stock prop nut and washer. I just want to thread a Higley spinner nut on. I think that there will be about 8 threads for the Higley spinner nut. I did not tighten the prop shown in the pictures. Things are going to compress a bit once I crank the prop nut down tight.

I hope that the folks intending to use a spinner find the dimensions useful. That crankshaft sure is "miserly" as hilleja pointed out.

Moses

edit: Hey lcgj ... you're a machinist ... do you think it is safe to thread the Higley spinner nut onto the end of the crankshaft if I only have about 8 threads.