A friend of mine had to twist 20 foot lengths of 1/2" square. He used
his small farm tractor. He made a "chuck" that fitted his PTO shaft.
He clamped the 20 foot length of square bar to the chuck and slid an
(almost) 20 foot section of half inch water pipe over the bar and
clamped the other end of the bar to a post 20 feet away. He mounted a
veeder-root counter on the back of the tractor so he could count
revolutions of the PTO shaft. He fired up the tractor and, at an idle,
gently engaged the PTO, letting it run until he had the required
number of turns.

Done cold, you are assured of equally spaced twists (just don't
start-stop). Done hot (as we blacksmiths often do it) you get a tight
twist where it's hottest and less twist where it is cooler. This
usually means that where the ends are suppported, they cool quicker and
twist less. Part of our training is in teaching how to correct for
these problems. One advantage of hot twisting is that one can make
good looking tighter twists with heat.

Pete Stanaitis
------------------------
SteveB wrote:

I want to spiral some small square stock. Probably 1/4" and 3/8" dimension.
What is the easiest practical way to do this? Hold one end in a vise and
twist the other with a crescent? How do I keep the whole thing straight, or
do I straighten it later? I want to spiral sections along a longer piece
rather than spiral the whole length.

And when I do want to spiral the whole length, will it spiral equally along
the length?

Steve