Don Foreman wrote:
On Sun, 10 May 2009 22:01:24 -0500, cavelamb
wrote:

You know those magic telescoping poles that can lock?

Useful for boat poles, spinnaker and jib poles, or changing light bulbs.

Anybody have a clue how these things work?

They're slightly elliptical, so they sort of cam lock when the mating
parts are rotated relative to each other.

I think you are on to it, Don.

I'm playing with a small Forespar jib pole.
It usually locks in 1/4 turn but sometimes misses and rotates for a while.

I was thinking about using something like that for a tiller lock.

Either that ot something like a turnbuckle with opposite threads to screw in and
out.