On Mon, 22 Mar 1999 14:55:53 EST, you wrote:
....
> In all cases, the nuts on the long bolts through the mast clamp had
>loosened up.
Some other possibilities, you may have eliminated them.
1) stretch of the long bolts, detectected by comparison with new ones.
2) some small deformation of the mast clamp due to stress.
3) Mast clamp digging into the mast a bit, enough to loosen the nut.
4) Deformation of the mast.
5) Really needed to be set with a torque wrench and wasn't.
5a) Factory torque setting not high enough or as high as possible with
the hardware isn't high enough, see 1) & 2).
If 1) then higher grade bolts called for
2) then Orion needs to go to work & improve clamp
3) then a retightening (retorquing) after 3 months, similar to
some automotive procedures on new cars.
4) then beefier mast.
5) Assume factory has torque specs?
5a) Into 1&2 answers probably.
Your further thoughts?
>And all of these nuts were the nylock ones supplied by the
>factory and also had spring lockwashers. These were both versions - the fine
>threaded and the coarse threaded ones so they are both subject to the same
>problem.
>
> While re-tightening them is great, I think it is inevitable that they'll
>loosen up again. In the case of the 2L 75M, it went through almost 2 winters
>before coming loose.
>
> Anyone using this rotator should plan on taking added precautions to
>prevent this. In my cases, I'm going to double-nut everything. Another option
>would be to use some Locktite (sorry - I can't remember if it's the blue or
>red to use). Or do both. In any case, you won't be sorry.
>
>Cheers, Steve K7LXC
>http://www.championradio.com
73, Guy
--. .-..
Guy Olinger, K2AV
k2av@qsl.net
Apex, NC, USA
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