Hi Steve,
Tnx for putting thru the post even though I blew the setting on the from
tab. I usually use the qsl.net setting so my Eudora program automatically
filters them into the Ham Stuff basket, rather than the other business, and
personal things I get.
To reply to your questions: I was thinking Chrom-moly because that is what
I have always heard is the strongest and lasts the longest.
The application is to top the 89 foot crank up by U S Tower. At the top
when nested the tower is about 27 feet I believe. I plan to tilt it over
for antenna installation and maintenance.
Antennas to be installed are a German Antenna a little larger than the C31
by Force 12, a dual band 17/12 meter antenna also similar to the Force 12
version, but heavier, and finally an M2 2 element 40 meter beam. I do not
know the exact weights just yet except on the M2 which is their published
figures.
I listed Chrom-moly first then put or similar because I figure with the
torque of side bending when I do antenna maintenance, and the heavy winds
here--We live on Lake Huron and I recently lost a tower that was
conservatively loaded when our winds spiked to over 90mph.
I would certainly love to save some money if there is an alternative that
would be safe and last an anticipated 20 years.
Thanks again, and I appreciate any recommendations u may make.
73 de Frank W8HO
By the way: at the end of my conversation with the local dealer, he
revealed that all round stock is special order and would be best ordered
elsewhere--though he didn't know where.
At 11:00 AM 1/10/2002 -0500, you wrote:
>In a message dated 1/10/02 6:43:00 AM Pacific Standard Time,
>owner-towertalk@contesting.com writes:
>
> > I am in need of a top quality mast for a tower installation. I purchased
> > the tower from the widow of a SK. He only had a short (approx 10 foot)
> > mast on the Tower, yet it has a full mast raising fixture installed. I
> > would like to replace this mast with a 20 foot long Chrom-Moly or similar.
>
> First things first. Why do you think you need a chromoly mast ($$$)?
> Most
>hams who think they need chromoly really don't need to spend that much money
>for a mast.
>
> What's your county windspeed rating? What's your proposed antenna
>installation? What kind of tower is it?
> >
> > Anyone out there know of a steel tubing dealer in the Detroit area, or as
>a
> > second choice Chicago area. I live 110 miles north of Detroit and would
> > like to keep my shipping costs down.
> >
> > An additional question, how do I communicate the Ham language of a 2"
>O.D.,
> > 1/4" wall Chrom-Moly mast (or whatever the next step down would be) into
> > the professional language that these tubing manufacturers use? I
> called a
> > local dealer and we could barely understand each other. He kept wanting
>to
> > know the application that the tubing would be used for yet he had no idea
> > what I was talking about when I described the application.
> >
> Hmm, what you want to buy is tubing with the necessary yield strength
> for
>your application - I don't know why the person you were talking to didn't get
>the picture (Maybe he/she didn't know much. They didn't know what a 2" OD
>1/4" wall chromoly mast was? I'd talk to someone else that knows what they're
>talking about.). My MARC (Mast, Antenna, and Rotator Calculator) program does
>mast calcs and gives you the needed yield strength required (available from
><A HREF="http://www.championradio.com">www.championradio.com</A>). Typical
>ham HF stacks and moderate winds up to 80MPH or so will require something
>like 60,000 psi yield strength which corresponds to an SAE 1026 or 1027
>carbon alloy steel which most tubing suppliers seem to stock.
>
>Cheers,
>Steve K7LXC
>Tower Tech
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