[TowerTalk] Plumbing a tower with a plumb bob

Jim Hoge knowkode at verizon.net
Fri Jul 30 07:45:45 PDT 2010


The purpose of the water filled bucket is to dampen the movement of the plumb 
bob. This does nothing for the effect of wind upon the plumb line. Given the 
length of the line,  the weight of the plumb bob, the drag of the line, and the 
windspeed, there may be some effect on an accurate reading. I use a fishing line 
such as Firewire for my plumbline. The Spectra line has almost no stretch and 
the tensile strength is amazing for its diameter, reducing its wind 
profile/drag. One cautionary note when working with this stuff, be very carefull 
with it. Special knots are required and you do NOT want to tighten this stuff 
with your hands and fingers. It will cut right through them. 


As for the best method to plumb a tower, it employs the use of a pair of 
theodolites, set  90* apart from each other, relative to the base of the tower.

73 and be safe,
Jim W5QM


More information about the TowerTalk mailing list