Grant Erwin wrote: used to heat crude oil in the bottoms of tankers so it
could be pumped out.(clip)
^^^^^^^^^^^^
What you are describing, Grant, is a way of making helical coils. What I
think Steve is looking for is twisted square stock, like that used as
pickets in wrought iron railings. I have done lots of this, and it is
pretty easy. You hold one end from rotating, in a vise, say, and twist the
other end with a large wrench. A large double-handles tap wrench is best,
because it balances the forces, so the metal stay straight. You need to slip
a piece of water pipe over the square stock to keep it straight. If you
need to twist only a section of a longer piece, let the material stick out
the other side of the vise, and past your wrench.

I have also done it with an electric pipe threading machine. You weld a
short square section at one end of your pipe, to apply torque to your square
stock. You clamp the piece of pipe with the square end away from the
rotating chuck. If you turn on the threader, the pipe and the square stock
turn together. If you put a wrench on the stock where it comes out of the
pipe and the chuck, you have the far end turning and the near end stopped,
so you will make your spiral.

Yes, they come out uniform.