My question: Do torque bars (TB) do any good on a Rohn 45 tower?
The TT archives show this issue was discussed before and my posting
will summarize the old info and ask if there is any new wisdom.
9/95:
W7NI did a summary of descriptions of guying used by many. He
also quoted a Rohn engineer as saying that the TB did nothing.
6/96:
AA7BG asked (as I do below) why 3000# shackles are used on 6700# guys?
N0YVY said MAYBE(!) it's how they're rated. MAYBE the the guys are max
load while the 3000# shackle is working load and MAYBE 6000+# max.(?)
3/97:
KF7E said his TB saved his Rohn 25 when many ham and a commercial
went down during a hurricane.
4/99:
K7LXC discussed logic of why Rohn discontinued the TB but brought
it back because the Hams wanted them.
Now my observation. The Rohn torque bar (TB45) used with the guy
assembly (GA45G) only has a 1/2 inch hole. This hole will just accept
the 7/16 inch pin of a 1.5T (3000 pound) shackle. But, Rohn recommends
1/4"EHS (6700 lb) guys. Seems strange to build a spec guy rated at
over 6000 pounds and then conntect it to the TB with a 3000 pound
shackle!
A work-around is to discard the torque bar and use a 3.25T (6500 lb)
shackel around the 5/8" torque bar bolt (hardness= 6) on the guy
assembly. Sounds reasonable to me. Any newer information? (I'll
be using a BPC45G base plate and a 3/4" pier pin so the tower will
free to release some torque energy on the base.)
73, Dick, K3DI
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Dick's lifetime address is k3di@arrl.net
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