a plumb bob, using 'piano' wire will support a VERY substantial weight and
hang fairly still. This is how we installed elevator rails.
But:
The last few times I did towers, I went to my friendly RENT ALL shop and
rented a laser and tripod.
These are like the ones you use to hang suspended ceilings with.
Very cheap to rent, can be used in any wind conditions.
They are self leveling so you put the laser spot on the base of a tower and
let it run up the tube.
Only problem is if your tower is the type that has reduction sections.
But if you get the bottom sections straight/plumb.
Also, your excavator may have one. Many excavators use similar units to
maintain depth control.
And as a bonus, They are battery powered.
-----------------------------------------------------
Don't hate yourself in the morning, sleep until noon.
-----------------------------------------------------
W9OL, Bill H. in Chicagoland
|