PS>Thanks to all for the quick primer about pier pins.
PS>Here's a summary that might be useful.
PS>The purpose of the pier pin is only to keep the base from
PS>sliding and to allow it to rotate during installation.
PS>Any force on the pin is lateral.
PS>There is no need for threaded stock, no need to put a nut
PS>on the end, definitely no need to torque it so hard that a
PS>"J" is needed to keep it from rotating in the concrete. And
PS>with no nut on the end, no "J" or buried flat washers or
PS>anything else is needed to prevent the thing from being pulled
PS>out, because there is no pulling force present. As others
PS>pointed out, if a nut on the end becomes important to
PS>prevent the base from hoping off the concrete pad, you've
PS>probably got a big pile of junk now, not a tower.
PS>A galvanized cold rolled steel rod of the size recommended
PS>by Rohn is the thing to use. In other words, like the one
PS>Rohn sells! (my memory of it in the catalog must have gotten
PS>bent)
PS>Now I can concentrate properly on the worry that if I don't
PS>insulate my EHS guys they'll direct lightning down and weld my
PS>turnbuckles. So much to worry about, so little time :-)
PS>Regards,
PS>Pete
PS>KS4XG
If I use a 12"-15" galvi bolt in the cement as a pier pin with the
threaded end up.. I can assemble 3 sections of ROHN 25 on the ground,
with the 3 temporary guys loose,
set it vertical and place it on the base and threaded pier pin, apply a
nut, finger snug,
and the tower will stay put while I set the 3 temporary guys. Once the
temp guys are set properly, additional sections can be gin poled up and
set.. after the tower is fully installed I back off on the threaded pier
pin nut...
This is not my original idea... The local ROHN distributor suggested
it....
All metallic guys must be grounded at the bottom... I bond the EHS guy
wire above the
big grip and turnbuckle, to the grounding system. Most of the current
from a lightning stroke will be diverted to my ground system and not the
turnbuckle or other dead end termination hardware..... I have not
encountered a (lightning) welded turnbuckle.
However ,I have encountered rusted threads on a turnbuckle where (I
suspect) lightning action had accelerated the errosion of the
galvanization.......
Stan, WA1ECF Cape Cod, MA FN41sr
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