Date: Thu, 28 Jul 2016 21:50:03 -0700
From: Grant Saviers <grants2@pacbell.net>
To: Jim Thomson <jim.thom@telus.net>, towertalk@contesting.com
Subject: Re: [TowerTalk] Lockwasher Comparison
Not sure what Rohn provides. My tower was a used AM BCB tower, a couple
of 10' sections were welded together after bolting. A BC engineer told
me this is common practice to increase conductivity. I do have some
stamped steel dished "kinda look like lockwashers" that came with the
guy anchors I bought from Rohn. They look pretty MM so I used Nordlocks
on the custom shaped U-bolts that go around the tower legs and bracing
at the same time. Just had a complete inspection after one year,
everything was tight.
Standard practice is to put the leg bolts in nut up, so when it falls on
the ground you see the nut is missing or that the bolt isn't there. Or
worse w/o your hard hat if it is a 5/8 x 2". If you can apply the rated
torque of 90 to 120 ft-lbs for waxed + galvanized bolts they might not
need locking washers, but the Nordlock insurance is pretty cheap
compared to everything else. A plain A325 5/8 needs 220 ft-lbs.
http://www.portlandbolt.com/technical/bolt-torque-chart/
Several articles I've read other than the Nordlock video/data seem to
agree that split ring washers are about useless.
I've never seen hot dip galvanized internal or external tooth
lockwashers. I use machine screw sizes internal ones, mostly on K-nuts
(KEPS) for electronics.
Grant KZ1W
## Per that chart from Portland bolt ( same place I bought my 12 x anchor
rods from)
you will notice that way less tq is required if the threads are lubricated....
like with
never seize goop. Marine grade never seize + nordlocks, whether galvanized or
SS
bolts + nuts used, would be the ticket. Look at G8 bolts...say .375 size.
Lubricated,
they only require 1/2 the tq vs no lubricant used. Ditto with .625 bolts, (
106 vs 212 ft lbs).
## In the end, you are after clamp load.. not tq. For stuff like the flange
plates used on R-65,
you want to mash the surfaces together, and by lubricating the bolts 1st, then
you dont require any where
near the tq of the same bolt...that’s not lubricated. I use never seize on
lugs on my car..and slightly less tq.
They dont loosen up, yet are easy to remove, when I swap to rain tires in the
fall.
Jim VE7RF
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