By the time the aluminum wall is thick enough to give the equivalent
strength of something like 1026 steel, you have lost the weight benefit of
aluminum. As for irrigation pipe, referring to the LXC prime directive and
its corollaries, pipe is for holding liquids and has a pressure rating, not
a load rating. Steel (and aluminum) tubing has a load rating.
Mike / W8DN
----- Original Message -----
From: "Gary Ingram" <kb7fci@cdsnet.net>
To: <Towertalk@contesting.com>; "wi8w" <rtty@comcast.net>
Cc: "Gary Ingram" <kb7fci@cdsnet.net>
Sent: Monday, August 04, 2003 8:56 PM
Subject: Re: [TowerTalk] mast recommendation
> Why don't you use aluminum tubing as most hams do. If your aluminum
> dealer does not carry it check on irrigation pipe from a farm supply
dealer.
>
> 73,
> Gary Ingram
> Merlin, OR
> http://home.cdsnet.net/~kb7fci/
> All mail scanned by Norton 2003
> ----- Original Message -----
> From: "wi8w" <rtty@comcast.net>
> To: <Towertalk@contesting.com>
> Sent: Monday, August 04, 2003 4:49 PM
> Subject: [TowerTalk] mast recommendation
>
>
> > Living in Grand Rapids, MI with a population of somewhere near 1 million
> > people you would think that finding a length of pipe for a mast would be
a
> > easy task...not so.
> >
> > I have spent the last week calling every steel dealer both in new and
used
> > steel for a chunk of 2 inch OD 1/4 inch wall 4130 pipe about 24 feet
long.
> > Did I find anyone who could supply it?...nope. All said it was special
> > order and they could not guarantee 24 feet. best they could do is
> something
> > random betweek 17 and 24 feet Special order meant that not only did I
> have
> > to pay for the pipe (around $16 a foot) but I would have to pay the
> shipping
> > (about $300 for a 24 foot length). They all said that I could buy two
> > pieces (and pay the shipping) and weld them together to make the 24
feet.
> I
> > am not a big fan of nor do I know how to weld anything short of a
resistor
> > to a circuit board.
> >
> > Anyone have any suggestions for a substitute at about a 24 foot length?
I
> am
> > stacking the following:
> >
> > 2M/440 vertical
> > 19 element 440 beam
> > 20 element 2 meter twist antenna (10 vertical and 10 horizontal)
> > 5 elements on 6 meters
> > A4S tribander
> >
> > in that order top to bottom. Yep it is going to be tight and the first
10
> > feet of the mast will be inside the tower
> >
> > 2 inch OD seems to be the biggest I can go given the size of the thrust
> > bearing (TB-3) on the tower.
> >
> > thanks
> >
> > 73
> >
> > Thom WI8W
> >
> >
> >
> >
> > ---
> > Outgoing mail is certified Virus Free.
> > Checked by AVG anti-virus system (http://www.grisoft.com).
To: <towertalk@contesting.com>
> > Version: 6.0.502 / Virus Database: 300 - Release Date: 7/18/2003
> >
> > _______________________________________________
> >
> > 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
>
|