[Andrew Rowe]

Back in the day, steel companies over here imported 7/16" "centreless" ground rod. I think this was a medium tensile steel and I guess you would still get this State side. As Alex has eluded to , it would be far more cost effective to form the head by the rivet making method, ie. heating the end whacking with a former. We made rivets for the M3 Stuart Tank in an old railways rivet making machine, which all you had to do was cut the rod to length, heat the end, drop it in the holder, and pull the lever, and "wamo" , you had a rivet , so making a track pin is the same principle, just using a longer shaft. Cheers Andrew.