Date: Mon, 06 Dec 2010 14:29:39 -0500
From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
Subject: Re: [TowerTalk] Never-Seez and noalox?
I'd not use any lube on tower joints, or any material that would reduce
the gripping action of the leg overlap as that would reduce the over all
tower strength and put more load on the bolts, which could lead to the
elongation of the bolt holes.
Also when use on bolt threads the torque required for a specific linear
pull on the bolt is reduced substantially. In compression on a tower
leg never-seez on the threads can lead a greatly increased crushing
force on the tower legs. That needs to be taken into account when used
on tower bolts.
## There is nothing wrong with using never seize on tower leg bolts, done all
Portland bolt engs tell me that when bolts are lubricated, you need no where
torque to get the same amount of tightness. Tightness and torque are 2 x
EG: a 3/8" g-5 bolt requires 38 ft lbs of torque when 'dry'..... but only
23 ft lbs when
lubricated. Now if Joe ham lubricates the bolts [and mating nuts]... and uses
38 ft lbs of
torque, you will have over tightened the bolt ! The engs also told me that
to use those
max torque figures they provide for the bigger bolts with caution..esp when UN
They tell me they break bolts all day long in the lab, when those UN lubricated
numbers are used. I lube all bolts [ and nuts] with lockite brand never
seize. The marine grade
brand offered by most 'never seize' makers is the best you can get. Made
for fresh and salt water
environments. [IE: rain for typ ham use].
## On both tower legs bolts like rohn 45-55 legs..and also typ al booms
used for ants, there is no need
to crank bolts super tight. You get em so tight, and after that, the
tightness drops off... since you are then
just crushing the tubing. On F-12 al booms, they use a combo of 3/16" solid
AL rivets and 1/4" SS bolts
[with SS nylocks]. I supplement the 1/4" SS bolts with another 8 x 3/16"
solid AL rivets.
## I use never seize on all SS bolts and screws, when used outside..esp when
SS nylocks used, other wise
SS will gaul the threads.
later... Jim VE7RF
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