On Tue, 28 Dec 2004 19:10:01 +0000, John Daragon
wrote:

Does anyone have any idea what this is called and where I might buy it from

Isaac Lord. They're called barrel bolts - you buy them as two pieces;
round nut and bolt. There are also different head shapes for flush or
surface heads, or tubular female bolts for a direct connection between
components.

Screwfix sell a few, but much smaller range. In particular they only
go to 100mm or so in length, and Isaac Lord go to 150mm.

Always insert the nut part into a through hole, not a blind hole.
Blind holes need to be exactly the right depth and are a pain to get
the alignment right. A spare bolt with the end ground to a point is
also a useful alignment tool.

Design your workbench framing joints so that each is pulled together
by two of these bolts, spaced as far apart as possible. Using a single
bolt just isn't rigid enough against racking.