1. keep hands and feet clear of the mast at all times.
2. make sure thrust bearings are tight, add a muffler clamp or two above one
of the thrust bearings just in case they don't hold.
3. remove rotor
4. attach come-along to bottom end of mast
5. make sure wires taped to mast are out of the way and move any beam on the
mast up so that it won't jam the mast.
6. tighten come-along until it removes weight from thrust bearings.
7. move muffler clamps up a foot or so and retighten.
8. loosen thrust bearings
9. SLOWLY lower the mast with the come along until the muffler clamps rest
on the thrust bearing again. If at any time the mast doesn't move down as
you release the come-along immediately pull it back up with the come-along
and figure out why it wasn't moving, do not let the come-along have any
slackness in its cable!
10. tighten thrust bearings
11. re-adjust come-along position if needed to allow next lowering step.
12. repeat 5 through 11 as many times as neede to lower the mast.
No, this is not a fun process. It is slow and must be done very carefully
or you can be easily injured.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of AG5WREFL@aol.com
> Sent: Friday, July 08, 2005 16:21
> To: towertalk@contesting.com
> Subject: [TowerTalk] Procedure to lower a mast
>
> I have a 24ft chrome moly mast on my 100ft Rohn 45 tower. 10ft of the
> mast
> are in the tower and held by two thrust bearings. 14ft are above the flat
> top
> section with a Hygain TH7 mounted about a foot above the top section and a
> Cushcraft 402CD mounted about 12ft above the top section.
>
> I need to get to the 402CD and therefore will need to lower the mast.
> Since
> this mast is quite heavy, I'd like to know a safe procedure to do so.
>
> 73, Greg AG5W
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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TowerTalk mailing list
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