mrcheerful wrote:

In view of the high volume, you need something faster than winding nuts on.

For a volume job like this I would use two nuts cut in half that are welded
to disposable vice jaws, that way you have a fast way to clamp without
damage to the threads, you would also be likely to incorporate a length stop
at the same time.

Yes that sounds the best method yet. Except that we seldom have such a
large run, and making such a device for each size and type of rod that
we use, and finding them again a year later would be a problem. Whereas
I can easily cut another couple of nuts.
The rods need to be only 2 inches long, and it was quite quick to just
slacken the vise and screw the rod along a couple of inches. Having a
length stop risks jamming the bandsaw blade when the cut piece of rod
falls off. I'd need to have a length stop that swings out of the way.