i hve yet too see an unpinned mast that dids not eventually
rotate in the clamps......
pin or not to is the question........i mostly do not as i wud rather
re orient the beam time or tw9 a year than tear up a rotator....
blew the gears outa
a coupla of hdr 300's a few years ago.....before they beefed up
the gears!! for small arrays like a tri-bander i wud pin...
w7gg
----------
> From: tgstewart@pepco.com
> To: k0wa@southwind.net; towertalk@contesting.com
> Subject: Re: [TowerTalk] drilling chromoly es similar pipe
To: <towertalk@contesting.com>
> Date: Tuesday, July 01, 1997 4:30 AM
>
>
> Yeah, I saw that. I dont care for the idea of using rubber in a mast
> clamp. I doubt it will hold very long...at least around here.
> Rubber is not a particularly long-lived product. Also, if you do that and
> add it to the cradle (in addition to the clamp), you'll throw the mast off
> center. My goal is and always will be to install something to last for as
> long a period as possible without requiring maintenance, and that sounds
> like high maintenance to me. I still say that if you have the clamp
> tightened properly and add the through bolt, you are not going to have any
> problems as long as you havent overloaded your rotator. (If you have a
> Yaesu rotator, all bets are off!) It's also important to pay attention to
> dynamic balancing, which will go a long way to keep things from spinning in
> the first place. Then if you still have problems, maybe it's time for a 3
> inch mast!
>
> I think if you have a tight clamp, with a hardened thru bolt in a chromoly
> mast and you shear something, you've got a design problem.
>
> 73, Tyler K3MM
>
>
>
>
> To: Tyler G Stewart/BENN/CEC
> cc: towertalk@contesting.com
> Subject: Re: [TowerTalk] drilling chromoly es similar pipe
>
>
>
>
> Tyler....
> Agreed about the bolt...but...most people believe (wrongly) that everything
> will stay the same. When you have wind, rain, sleet, snow, and various
> other forms of weather above the roof line or tree line, something is
> stressed. If you use a bolt through a hole in the mast...the bolt or the
> mast WILL give. I understand that the bolt is not meant to take ALL the
> torque, but people rely on them way to much. I have seen bolts break and
> holes wallow out. Just a hugh expense and an accident waiting to happen.
> Never...NEVER....drill a hole in a mast. It is not worth it. The rotation
> of the beam will severelt over tax the bolt and the mast over time.
> Guranteed. K7LXC came up with a neat idea I had never heard of..and that
> is
> to wrap the mast that goes into the rotor with some rubber and tighten the
> rotor down. I could see that gripping better than metal on metal. Never
> used the technique...but plan to shortly.
> Of course...this is IMHO.
> Lee
> k0wa@southwind.net
>
> At 04:59 PM 6/30/97 -0400, you wrote:
> >
> >Negative.
> >
> >The bolt thru the mast isnt meant to take all the torque. It's only there
> >for insurance. In case the clamp slips, it's not going to rip out coaxs
> >and things like that. It should, however, assist the clamp in some small
> >amount...just dont rely on it exclusively.
> >
> >73, Tyler K3MM
> >
> >
> >
> >
> >
> >k0wa@southwind.net on 06/30/97 12:21:10 PM
> >
> >To: k4isv@westky.com
> >cc: towertalk@contesting.com (bcc: Tyler G Stewart/BENN/CEC)
> >Subject: Re: [TowerTalk] drilling chromoly es similar pipe
> >
> >
> >
> >
> >At 01:15 AM 6/30/97 -0500, you wrote:
> >>i am doing some antenna repair and part of the repair requires drilling
> >>heavy mast. by heavy i mean 1/2" wall thickness chromoly steel. after
> >>burning up several bits and a few $$$ let me pass this tip: use a
> >>masonry bit ( carbide tip ), lowest speed on drill press, and lot of
> >>oil. the most expensive bit i have used only did about 1/8 inch deep
> >>( cost about $12 ) and the least expensive was the carbide tip masonry
> >>type. it has taken me over 4 hours of drilling to make a 5/8 hole in
> >>some of this stuff but i am betting it wont bend!
> >>
> >>put em up high and hope they stay up!
> >>
> >>73, de bud
> >Opinion: I don't like any holes in my mast. Now, I have never use
> >Chrome-Molley masts and I know they are hard, but I have used steel masts.
> >I have drilled holes to connect masts together..etc..etc...and the holes
> >wallow out over a period of time. The beam then really moves in the wind
> >and damages the rotor. I have tried all sorts of schemes to stop this
> from
> >happening...using shoulder bolts, heating the metal and pressing on the
> >bolts, etc...etc. It will wallow out. The best solution is
> >never..NEVER...drill a hole in a mast.
> >Lee
> >k0wa@southwind.net
> >
> >--
> >FAQ on WWW: http://www.contesting.com/towertalkfaq.html
> >Submissions: towertalk@contesting.com
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> >
> >
> >
> >
> >
> >
>
>
>
>
>
>
> --
> FAQ on WWW: http://www.contesting.com/towertalkfaq.html
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