I also pin the mast which holds a TH7 and Cushcraft 402CD turned
by a T2X. Been up there almost 10 years. A few years ago, while
up on the tower, I noted the bolt was cracked in half! I forget the
exact alloy, but it was a high strength steel with some Beryllium in
it. I did replace it with another bolt, and so far, it's still in one piece,
last I checked.
Regarding drilling, I first tried with a standard bit - wouldn't dent the
stuff. Then, bought a Cobalt tipped bit labelled "for hardened metals
including stainless steel." With some cutting oil, went thru like
butter.
73 Barry
On 6 Sep 99, Jeff Singer wrote:
>
> Hi all,
>
> I use Yaesu rotors and big KLM antennas, and have tried it both ways.
> Obviously, there is no way to keep the KLMs from turning in the puny Yaesu
> clamps, so I've opted to pin. However, if you use Yaesu's supplied pin, it
> will simply shear off on both ends at the first gust of wind, so you MUST
> use SS bolts.
>
> Yes, the 4130 was a bear to drill through, but if you start with brand new
> titanium-tipped bits and go from smaller to larger while using some
> lubrication (and you exercise some patience, as well), you'll eventually get
> through. And I never have to re-orient the antennas (KT-34XA & 40M4 on same
> mast) anymore. They used to spin like tops!
>
> 73 de Jeff K2KV
> k2kv@reallybig.com
>
> > -----Original Message-----
> > From: owner-towertalk@contesting.com
> > [mailto:owner-towertalk@contesting.com]On Behalf Of K7LXC@aol.com
> > Sent: Monday, September 06, 1999 6:05 PM
> > To: clewis@ro.com; jackcolson@x-press.net; TowerTalk@contesting.com
> > Subject: Re: [TowerTalk] To pin or not
> >
> >
> >
> > In a message dated 99-09-06 17:49:54 EDT, clewis@ro.com writes:
> >
> > > But, Steve, Yaesu's instructions are very explicit in telling
> > us to pin with
> > > the bolt provided! When I, as a believer in non-pinning,
> > called Yaesu's
> > tech
> > > support, I was told I must pin. Actually, considering that the
> > 800SD(X) has
> > > no brake, this might be the proper thing to do. We can either
> > crank the
> > hell
> > > out of the clamps with no pin, and risk cracking them, or
> > snug-em up gently
> > > per Yaesu's directions and pin. Wind blown rotation in the
> > case of these
> > > rotators will just change its azimuth since there's no brake ("braking
> > > torque" is a result of gear-reduction and friction). With no
> > brake, there
> > > should be less risk of gear failure. So...I pinned. When the
> > wind blows it
> > > around, I just turn it back where it belongs. Just trying to follow the
> > > 'Prime Directive' ;>).
> >
> > Okay, okay - I'll concede the point.
> >
> > The original poster asked about *his* situation. I stand by
> > my advice to
> > 'not pin' since he's dealing with 4130 which will be a bear to
> > drill. It's
> > more of a practical consideration to me. I guess with the Yaesu
> > 'prone-to-break' clamps, they're just ensuring that the mast won't slip
> > inside the clamps.
> >
> > Cheers, Steve K7LXC
> >
> > --
> > FAQ on WWW: http://www.contesting.com/towertalkfaq.html
> > Submissions: towertalk@contesting.com
> > Administrative requests: towertalk-REQUEST@contesting.com
> > Problems: owner-towertalk@contesting.com
> > Search: http://www.contesting.com/km9p/search.htm
> >
>
>
> --
> FAQ on WWW: http://www.contesting.com/towertalkfaq.html
> Submissions: towertalk@contesting.com
> Administrative requests: towertalk-REQUEST@contesting.com
> Problems: owner-towertalk@contesting.com
> Search: http://www.contesting.com/km9p/search.htm
>
--
Barry Kutner, W2UP Internet: w2up@mindspring.com
Newtown, PA FRC alternate: barry@w2up.wells.com
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
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