[Elecraft] RF on pipes

[Clint]

This is a bit OT but it does concern my K3. Hopefully this will not open too big of a can-o-worms.

As an experiment to try and achieve a very low impedance ground system, I am using 1 inch rigid copper tubing for my station and Vertical Antenna grounds and ½" copper refer tubing to tie together my ground rods and the mains ground. 

ANYWAY, I know that RF "travels" on the outside skin of a conductor. My question is: Does it also travel on the inside skin? In other words, would the impedance be the same on a round hollow tube as it would be if the tube was slit and laid out flat?

 

Thanks,

 

Clint KI6SSN