I used a thin brass tube from K&E and soldered two end washers on the tube.
The end washers were made from thin PCB material (.030).
I used heavy duty scissors to cut the washers out.
Bill Goodrich ( aka DHD at billgoodrich.com ) did some of the work on this.
Hire him ..... he is good at tech stuff.
We used a battery drill to turn the tube as we wound the wire on. Hot glue anchored the wire to allow us to get started. One guy operated the drill and the other guy guided the wire in the tube.