There’s no magic or guessing necessary. Get the software that calculates the
forces on the mast and tower and make sure you don’t exceed the rated
capability. Towers are rated for so many square feet in so much wind at a
distance above the top. Combine all the forces to that point and you’ll know
whether it’s ok or not.
Ken K6MR
From: Gary Schafer<mailto:garyschafer@largeriver.net>
Sent: Monday, November 23, 2020 10:39
To: 'David Winarsky'<mailto:david@winarsky.com>; 'Dick
Williams'<mailto:richardk8ztt@gmail.com>
Cc: 'towertalk@contesting com'<mailto:towertalk@contesting.com>
Subject: Re: [TowerTalk] Cut off extra 7 ft of mast or leave it?
I don't think that I would put a 20 foot mast on top of a crank up tower!
What type of mast do you plan to use? Aluminum, Molly etc?
I have that same tower and it would worry me with that high of a mast
especially when tilting it over. A lot of stress there.
73
Gary K4FMX
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On
> Behalf Of David Winarsky
> Sent: Monday, November 23, 2020 8:18 AM
> To: Dick Williams
> Cc: towertalk@contesting com
> Subject: Re: [TowerTalk] Cut off extra 7 ft of mast or leave it?
>
> Thanks everyone for all the great comments and advice! It
> sounds like a lot of people have a similar setup and are
> actually utilizing the extra space space. I wasn’t sure the
> extra length of mast would be stable enough to hold another
> antenna on its own, but based on this thread I’ll plan to put
> a 3 feet of the mast in the tower (with the rotator plate 3
> ft down as Karl advised), put the Steppir a few feet above
> the top of the tower, and the JK40 all the way at the top.
>
> By the way, one additional question I forgot to ask— I had
> been advised to rotate the JK40 90 degrees from the Steppir
> to avoid interaction between the two antennas. Do you folks
> advise the same?
>
> Thanks again,
> David K6ZD
>
> > On Nov 22, 2020, at 21:51, Dick Williams
> <richardk8ztt@gmail.com> wrote:
> >
> >
> > Dave,
> >
> > If you are not planning on stacking another antenna on the
> tower, why not move the 40M dipole up higher and utilize the
> additional 7 ft to get the 40M rotatable dipole a bit higher
> up? That tower seems to have similar specs to my old US
> Tower HDX-54 that I have had up close to 20 years. Like
> yourself, I have a 20 ft mast and the rotor (Tailtwister) is
> mounted in the tower with 3 or so feet of mast in the tower.
> I use the tower to hold two Force 12 Magnum antennas. One is
> a 7 element 12 M beam about 1 ft above the top of the tower,
> and the other is an 8 element 10 M beam about 3 ft from the
> top of the mast (the U Bolt and saddle that holds the truss
> cable for the 10M beam is at the top of the mast). I live on
> top of a hill, and have had winds in excess of 70 MPH on more
> than one occasion.
> >
> > Have fun erecting the tower. For the first time since I
> erect it, I had to do some maintenance last week, and it was
> sure nice to be able to lower it down!
> >
> > Dick, K8ZTT
> >
> >> On Sun, Nov 22, 2020 at 9:38 PM Gary K9GS
> <k9gs@gjschwartz.com> wrote:
> >> I'd have to study this a bit more but why not put a 3 ele
> 6m beam at the top and stack with the DB11 on 6m?73,Gary K9GS
> >> -------- Original message --------From: Raymond Benny
> <rayn6vr@gmail.com> Date: 11/22/20 10:23 PM (GMT-06:00) To:
> wesattaway@bellsouth.net Cc: Tower Talk
> <TowerTalk@contesting.com>, David Winarsky
> <david@winarsky.com> Subject: Re: [TowerTalk] Cut off extra 7
> ft of mast or leave it? You paid big bucks for a good mast.
> 7ft sticking up won't hurt a thing.Besides, you may want to
> add another antenna in the future.Ray,N6VR/W7YAOn Sun, Nov
> 22, 2020, 7:56 PM Wes Attaway <wesattaway@bellsouth.net>
> wrote:> I would leave it in place because someday you might
> want to put a vertical> up there.>>
> -----------------------------------> Wes Attaway
> (N5WA)> (318) 393-3289 - Shreveport, LA> Computer/Cellphone
> Forensics> AttawayForensics.com>
> -----------------------------------> -----Original
> Message-----> From: TowerTalk
> [mailto:towertalk-bounces@contesting.com] On Behalf Of>
> David> Winarsky> Sent: Sunday, November 22, 2020 8:39 PM> To:
> TowerTalk@contesting.com> Subject: [TowerTalk] Cut off extra
> 7 ft of mast or leave it?>> I'm putting up my first tower, a
> LM-354HDSP with a Steppir DB11 and a JK 40> meter horizontal
> dipole, both in the same mast. I have a 20 ft 2 in OD mast>
> from Tashjian and am wondering whether I should cut off the
> unused length> or> leave it?>> Karl at Tashjian suggested I
> install the rotator plate 3 ft below the top> of> the tower
> and the DB11 2 ft above the top, with the JK40 8 ft above
> that> (10> ft from the top of the tower). That will leave 7
> ft of the mast unused.>> Do you folks recommend I leave the
> extra 7ft of the mast in place or cut it> off?>> Appreciate
> the input and any other comments or suggestions on my plan.>>
> 73,> David K6ZD>
> _______________________________________________>>>>
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