There are several grades of fence posts; the cheap stuff is Schedule 15 and
other choices go up to 83,000 psi yield strength.
The 2" (1.9" OD) 40+ that I use has a yield of 50,000 psi and a bending
moment of 14050 lb". Going up to the 2 3/8" OD bumps the bending moment to
24405 lb". Pretty healthy specs IMO and a good choice when DOM or chrome
moly isnt required. And since it is produced in huge quantities the cost is
fairly low.
Schedule 15 of similar 1.9" OD has a bending moment of 9100 lb". The next
size smaller is only 6830 lb".
Id warrant a guess that hardware/box store import fencing is far less.
I found the specs on the following URL, it covers a wide range of pipe and
tubing. www.wheatland.com
Carl
KM1H
Carl
KM1H
----- Original Message -----
From: "Julio Peralta" <jperalta@tampabay.rr.com>
To: "'jeremy-ca'" <km1h@jeremy.mv.com>; <K7LXC@aol.com>;
<towertalk@contesting.com>; <Eroddy4366@aol.com>
Sent: Friday, June 01, 2007 1:43 PM
Subject: RE: [TowerTalk] masts.
> Many years ago I stacked two 6elem 6M beams on that fence rail material.
> A small storm bent the mast just above the 1st antenna and we had a hell
> of a time getting it down. I would not recommend fence material for
> stacking antennas.
>
> Julio, W4HY
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of jeremy-ca
> Sent: Friday, June 01, 2007 12:13 PM
> To: K7LXC@aol.com; towertalk@contesting.com; Eroddy4366@aol.com
> Subject: Re: [TowerTalk] masts.
>
> I use 21' of 1020DOM 1/4" wall steel tube for 2 towers. However on
> another
> I have a 15' length of galvanized fence pipe. I believe it is called
> Schedule 40+ and it has supported a 3 el 20M monobander, a 38' boom 8 el
> 6M
> yagi at the top and a 28' boom 432 yagi in the middle. It is not cast
> iron
> and is both strong and light and cheap when I bought it 15 years ago.
> Never
> a problem here on this exposed hilltop rock pile.
>
> At a former QTH with less wind exposure I had a 20/15/10 stack of W2PV
> 4el
> monobanders on 20' of 2 3/8 OD galvanized cast pipe. Except for eating
> rotators (Daiwa and Create even using 2 thrust bearings) it survived
> just
> fine thru many northeasters, CAT 2 & 3 hurricanes and ice storms while
> on
> 100' of 25G.
> Im sure that there are many parts of the country that cast pipe would
> fail
> but dont discount it altogether.
>
>
> Carl
> KM1H
>
>
>
> ----- Original Message -----
> From: <K7LXC@aol.com>
> To: <towertalk@contesting.com>; <Eroddy4366@aol.com>
> Sent: Friday, June 01, 2007 9:46 AM
> Subject: Re: [TowerTalk] masts.
>
>
>>
>> In a message dated 5/31/2007 7:56:02 P.M. Pacific Daylight Time,
>> towertalk-request@contesting.com writes:
>>
>>> i need to install a new mast to support a t12 log antenna.i want to
> use
>> 10ft
>> of sch40 galvy pipe 2 inch in dia.anyone think differently.i had
> thought
>> about using sch 10 sprinkler pipe.thankyou
>>
>> Ouch - a recipe for disaster. Pipe - the definition of which has
> been
>> recently discussed - is not rated for strength and is heavy but not
>> strong
>> enough. A typical water pipe might have 35,000 psi yield strength.
> You're
>> probably going to need more than that; e.g. 50-60,000 or more.
>>
>> You didn't mention your local windspeed rating. If you don't know,
> you
>> can find it on _www.championradio.com_ (http://www.championradio.com)
>> under
>> "Tech Notes".
>>
>> I sell the MARC Program - the Mast, Antenna and Rotator Calculator
> -
>> for
>> ten bucks on the same website. It'll give you the info you need. And
> you
>> need tubing - not pipe.
>>
>> Cheers,
>> Steve K7LXC
>> TOWER TECH and
>> Champion Radio Products
>> Cell: 206-890-4188
>>
>>
>>
>>
>>
>>
>>
>> ************************************** See what's free at
>> http://www.aol.com.
>> _______________________________________________
>>
>>
>>
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>> http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
>
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