...Came in late to your discussion, but for permanent use (like to stay in
place for a few years or more), consider two-piece clamp-on shaft collars.
These are available in steel,
stainless steel, aluminum, etc. and are available up to at least 3" bore. They
aren't cheap, however, but will do a superior job. They can be found in the
McMaster-Carr cat. (probably
other places too) under "shaft collars". These have the advantage of not
putting a setscrew divot on a mast and if supporting a load on a bearing, the
force is evenly distributed.
I, too, would use muffler clamps for temporary use (as, e.g., in an assembly
procedure)..
73,
Tom - WA2BPE
EUGENE SMAR wrote:
> Larry:
>
> I did the same thing John did - used two back-to-back muffler clamps
> and a pair of straight carriage bolts to hold them together. However, you
> might have to saw off about a quarter-inch of each tab on the clamp saddles
> to they don't bump into each other when you put them around the mast.
>
> Before I installed them (one is atop the top bearing rather than using
> the set screws to help support the mast and antenna weight, and the second
> one is just holding onto the mast, so it's there when I need it), I cleaned
> them with degreaser, then sprayed them with cold galvanizing. For temporary
> use, not a bad surface treatment.
>
> 73 de
> Gene Smar AD3F
>
> ----- Original Message -----
> From: "W0UN -- John Brosnahan" <shr@medinaec.com>
> To: <Towertalk@contesting.com>
> Sent: Monday, August 04, 2003 6:55 PM
> Subject: Re: [TowerTalk] Mast Collars
>
> > An easy and cheap way to do this is to use back-to-back
> > muffler clamp saddles. Bolt them together with straight
> > bolts. Strong enough for most ham installations and
> > cheap. Only problem is that it is getting harder to find
> > plated clamps. Best shot is to find blister-packed clamps
> > rather than ones sold in bulk. Since they are on view the
> > manufacturers tend to make them look a little prettier.
> >
> > 73--John W0UN
> >
> >
> >
> > At 06:30 PM 8/4/2003 -0400, you wrote:
> > >Somewhere...recently...I read about using a 'Split Collar' to help hold a
> mast
> > >above the thrust bearing while extending the mast above the tower before
> > >installing the rotor. Hope this makes sense?
> > >Question here is where can one get those split collars?
> > >
> > >Thanks, Larry K1UO
> > >
> > >
> > >_______________________________________________
> > >
> > >See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> > >Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> > >any questions and ask for Sherman, W2FLA.
> > >
> > >_______________________________________________
> > >TowerTalk mailing list
> > >TowerTalk@contesting.com
> > >http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
> questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
> questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
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