Being familliar with the K&S line of telescoping tubing, I decided to try to make my own from their 1/16" brass tubing and 1/32" brass rod. 

The female socket contacts were made according to the drawing on the right.  After cutting the tubing to length, I slit the ends with a extra-fine tooth razor saw. 

Next, I de-burred the outside of the slit with a needle file and the inside of the slit by hand with a #67 drill.  I tapered the opening of the socket with a pointed motor tool bit.  A 1/16" drill might also work.

Finally, I squeezed the contact at the point indicated to make it a tight fit for the male contacts.

I soldered wires to the outside of the female contacts on the end farthest away from the slits, and pushed the contacts into 1/16 inch diameter holes drilled through a scrap of 1×2 lumber, which had been marked with colored paint to distinguish one hole from another. 

The male contacts are 1/2" pieces of 1/32" brass rod.  The wires are soldered to one end, and the other end I tapered with a needle file to make it easy to insert into the female.  The male contacts are not contained in a plug body, but are loose, like the plugs on an old telephone switchboard, and are inserted one at a time.

This page was composed in November, 2008.  If the plugs and sockets become a problem later on, I will update this page.