At 09:16 AM 11/11/97 +200, you wrote:
>> The issue I have with this senario is drilling the mast. I have done this
>> in the past, but if I had my druthers, I would never...never...never pin a
>> mast if I could help it. I don't care how tight you drill the hole, or how
>> hard the bolts are...the wind moving the beam around will wallow out the
>> holes and the whole thing will get loosy goosy. Once you get a degree of
>> arc (slop) in the mast, you will take out your very expensive rotor. Just a
>> warning...cause it has happened to me.
>Stan does not mention whether he pinned his mast, except to hold the
>two together near the top.
>
>I did pin mine, with no problems. I have two thrust bearings in my
>tower, as good engineering practice dictates, so there is no lateral
>force or weight on the rotator; only torque.
>
That is what will kill the mast....torque. The slightest misfit between the
hole and the pin, bolt, whatever, will allow the wind to blow things around
and wallow out the hole. I have wallowed out holes and sheared case harden
bolts. Ok, I live in Kansas and there is a lot of wind, but my rule is
never drill a mast and pin it because you will replace it in a year.
Lee
k0wa@southwind.net
>
>
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