Dave Hinz wrote:

So holding, then, is done with a shaft the diameter of the hole, and a
larger shoulder top and bottom, and a bolt for tension,

Exactly. I have some of those shafts. And they get more for each
diameter missing.


Is there a better way?

CNC ;-))

Ah. I'd like to revise my question to introduce a constraint of "for
the home machinist with 1960s technology" please.

I was kidding. :-)
If you look at old connection rods, and know what means they had, it is
clear how they did it and why they look the way they look.

There are also other forms of con rods. But this is the simplest form.
If you have a RT with a table (with one axis) sitting on top of the RT,
you can mill the outer form in one go. I don't have, but maybe ...


Nick, also no CNC
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