Steve Turner wrote:
Andy Dingley wrote:
On 14 June, 15:01, eganders wrote:
I need to make a spiral groove in a couple of columns.

You want one of these:
http://commons.wikimedia.org/wiki/Fi...y,_ 1925).jpg


You're right! Do you know where I can get one?


Maybe a little more reasonable:

http://www.timbecon.com.au/details/r...athe-8715.aspx