[TowerTalk] Tower Base Round or Square?

[Richard Thorne]

I'm finally getting some dirt work done in the next day or two at my new 
place which will include holes/concrete for my 45g tower.

I plan on using a pier pin install, so does it matter if the base is 
square or round?  The rohn book calls for a 2' 6" square hole 4' deep  
(I'm designing the tower based on 90mhp winds with a height of 120').  
It would be easier to use a 36" auger to dig the hole.  Since I'm going 
with a pier pin I don't see that there would be any twisting moments on 
the concrete base, it would only be there to hold the tower up.  But I'm 
not an engineer, hence the question.

Thanks

Rich - N5ZC