[TowerTalk] radial attachment to tower

[Richard W. Harris]

Hi,
I just finished putting down 56 radials for a 160M shunt-fed tower I'm working on.    Now I know why I put this off so long.
 
One question I have - I have an 18" square copper plate with holes drilled and tapped around the perimeter to allow attachment of the radials.  My tower is US Towers 72' crankup with a steel base (painted black). Tower of course is galvanized.  Tower attaches with 18 bolts to this painted steel base.  If I attach the copper plate to the steel base can I assume good connection from the tower through the 18 bolts or should I make some other connections from the tower to the copper plate?
 
Also, any suggestions how to attach the copper plate to the steel base.
 
Thanks much,
Richard - KJ7CU