Both clamps look more than adequate to the task. However, I see some
problems:
1. Steve, my M2 OR2800, which was bought new last year, has a bolt and
bushing in the middle of the base shelf that stick up about an inch above
the surface of the base plate. The bolt pulls the rotor output shaft up to
the base plate and can't be omitted. There's also a trapezoidal metal
fixture that slips over the bolt head and provides a handy way to center the
mast. The fixture can be omitted, but it's nice to have. Your clamp would
need a large hole in the center of its base plate so it could slip over the
bolt head and bushing. Even if there was a hole, I'm not sure there would be
enough clearance in your clamp to accommodate the fixture. Also, both the
stock clamp and Kurt's have elongated bolt holes that allow some slop in the
clearances. I don't recall offhand if the base shelf has elongated holes,
but I don't think so.
2. Kurt's clamp has a large hole in the center that's specifically designed
to accommodate the bolt and bushing. Don't know if the centering fixture
would fit, though. Given that Kurt's base plate has elongated holes, the
centering fixture would come in handy. But the big problem is it looks like
you wouldn't be able to retrofit Kurt's clamp into an existing system
without jacking up the mast or removing the rotor. The clamp is so tall I'm
not even sure it could be done by just removing the rotor -- i.e., you might
have to jack up the mast in any case. Not fun.
3. M2 specifically warns against pinning the mast to their rotor, and they
say it will void the warranty. Evidently, they feel that if the mast isn't
allowed to slip under extreme circumstances, it will tear up the inside of
the rotor. If Steve's and Kurt's clamps do what they say, then they'll be
just as good as pinning the mast. Therefore, their use will essentially
violate the rotor manufacturer's instructions. Violation of the LXC Prime
Directive?
(P.S. My stock mast clamps slipped a tad -- about 7 degrees -- this winter
in a very high wind. Because this is less than the rotor's allowed
overtravel, I was able to enter an offset calibration factor in the Green
Heron Rotor controller to compensate until I can climb up there and fix it
come springtime.)
73, Dick WC1M
> -----Original Message-----
> From: Dino Darling [mailto:dino@kx6d.com]
> Sent: Thursday, January 29, 2009 8:31 PM
> To: K7LXC@aol.com
> Cc: towertalk@contesting.com
> Subject: Re: [TowerTalk] Orion 2800 replacement mast clamp available
>
> Kurt has one too...
> http://www.k7nv.com/proppitch/id35.htm
> I've used Kurt's on his prop pitch rotors and they work great! All
> that surface area against the mast makes for an excellent system.
>
> Steve, I would like to see elongated holes to center the clamp for
> use of DX Engineering's saddle clamps.
> http://www.dxengineering.com/Products.asp?ID=14&SecID=1&DeptID=39
>
> The saddle clamps also give you a larger surface area against the
> mast. You could have used half as many clamps if not
> more. Unfortunately, those saddle clamps would move the center of
> mast away from true center and you now have binding issues. If you
> have time to make some minor changes, you have a winner of a product
> at a good price.
>
>
> Dino - KX6D
>
> At 03:59 PM 1/28/2009, K7LXC@aol.com wrote:
> >Howdy -
> >
> > If you're the owner of an M2 Orion 2800 rotator, chances are
> excellent
> >that your antenna system has slipped in the wind at some point. The
> factory
> >mast clamp has 2 fatal flaws: 1) the clamping teeth are not aligned
> and have
> >less than 0.5 square inches of actual clamping surface; and 2) the
> >nut and bolt
> >surfaces are dimpled which flatten over time so the fasteners loosen
> up and
> >the mast slips again. The Champion Radio Products clamp eliminates
> both
> >problems. They're $160.00 plus s/h.
> >http://www.championradio.com/misc.html
> >(http://www.championradio.com/misc.html)
> >
> >Cheers,
> >Steve K7LXC
> >Champion Radio Products
> >Cell: 206-890-4188
> >**************From Wall Street to Main Street and everywhere in
> between, stay
> >up-to-date with the latest news.
> (http://aol.com?ncid=emlcntaolcom00000023)
> >_______________________________________________
> >
> >
> >
> >_______________________________________________
> >TowerTalk mailing list
> >TowerTalk@contesting.com
> >http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
> >No virus found in this incoming message.
> >Checked by AVG - http://www.avg.com
> >Version: 8.0.176 / Virus Database: 270.10.15/1924 - Release Date:
> >1/29/2009 5:57 PM
>
> Dino - KX6D
> dino@kx6d.com
> (please note my new e-mail address and update your address books)
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|