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Old January 1st 05, 10:17 PM
H. Adam Stevens, NQ5H
 
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"Richard Clark" wrote in message
...
On Sat, 1 Jan 2005 14:06:25 -0600, "H. Adam Stevens, NQ5H"
wrote:

Richard
The tower's a 48' Trylon self-supporting affair.
The base, rebar cage, and additional rebar driven into the hole walls for
positioning are all welded together.
The contractor made damn sure the base will remain plumb during the pour.
I intend to use 3 - 6 additional rods outside the cage attached to the
legs
with big cable.
Not familiar with the term "Ufer"?
73
H.


Hi OM,

Concrete is conductive and with the large surface area presents quite
an electrode - the Ufer ground. Providing for a connection to its
metal interior insures you have access to this characteristic (and
with the rebar welded, insures that there will be no exploding
concrete at the J-Bolts due to current crowding if/when lightning
strikes).

73's
Richard Clark, KB7QHC


Hi Richard
Lightning and the practicalities (no J-bolts, tower leg extension into the
concrete, holding the damn thing still during the pour) pretty much require
all the metal to be welded together. Then I'll put several good rods around
the base a few feet out.
I've seen lightning strike concrete; blew a 3 foot hole.
73
H.