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Author Topic: Mast material  (Read 680 times)
KI4KFS
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Posts: 15




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« on: February 18, 2006, 10:20:16 AM »

I am trying to build an inverted "V" on the cheap and am trying to find inexpensive mast material. I have considered 1.5" diameter pvc conduit which is gray in color and will not stand out. However, I have found that at 20-30' in length, a mast made of this material is not very rigid. Any suggestions for an alternative, inexpensive material?

Thanks in advance!
Kevin - KI4KFS
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WA9SVD
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Posts: 2198




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« Reply #1 on: February 18, 2006, 01:18:33 PM »

The two sides of the "V" serve as a pair of guy lines.  To balance things you would need another pair at right angles to the "V" section, using non-conductive rope (good for a couple of years in weather) or phillystran, good for a lot longer.
    Two important considerations:  (OK, three!)

1.  You MUST use guy lines.
2.  At 20-30', you really should guy at two levels, not just at the top.  Otherwise, you get bowing in the middle, most likely resulting in rapid failure.  (You need to minimize any flexure or movement of the middle section as well as the top section.)
3.  If using such "flexible" pipe, don't attempt to do a "one-person" installation.  You will need to have at least two, perferably three people to support the mast before it is raised vertical in it's final position.

    I wouldn't really recommend using such pipe, but it can be done with care, and perhaps a bit of luck.  Just make sure it won't destroy anything if it fails (or falls.)  The PVC pipe you suggest isn't designed for the kind of strength necessary for an antenna mast.  Remember, safety is more important (and ultimately a lot less expensive) than saving a few pennies, or even dollars.
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KE4DRN
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Posts: 3729




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« Reply #2 on: February 20, 2006, 06:54:05 PM »

hi kevin,

Take a look at this item
# 5825901025 on Ebay,
new fiberglass mast tubes
mil surplus.  He is in PA.

I am just one of his customers,
the seller is good to deal with.

He also has aluminum if you like.

73 james ke4drn
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WB2LCW
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Posts: 108


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« Reply #3 on: February 22, 2006, 12:29:11 PM »

I use a push-up steel tv mast to support three
inverted v antennas at 28 feet. Cost about $30!

My local TV parts supply store has them up to I
believe 40 to fifty feet max hight.

My mast is bolted to a post in the ground and is not guyed..

It has been up about ten years so far..
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KI4KFS
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Posts: 15




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« Reply #4 on: February 22, 2006, 07:22:28 PM »

Thanks for all of the responses. Thanks for the fiberglass mast recommendation. I've checked out Ebay and have a bid in on a set.

Kevin - KI4KFS
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N3OYA
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« Reply #5 on: April 08, 2006, 04:49:53 PM »

I can also recommend the fiberglass masts.  These are support poles for military camouflage netting, and are very strong.  You can load quite a lot of pressure onto these before they'll fail.

That said, they're not designed for antenna support, so YMMV.  You'll also need to guy the mast, so you'll need ropes and guy rings.

Fair Radio Sales (visit: http://www.fairradio.com/antenn.htm) has, at the top of the referenced page, a kit for a (basically) 30' mast which contains the fiberglass polesets, stakes, guys rings, and ropes, all in a convenient rubberized carrying bag.  A bit more expensive, yes, but I'm thinking that by the time you add in all the other stuff you'll need to set up the eBay mast, you'll be close to the Fair Radio price anyway.

Also, you'll need some sort of base upon which to place the mast.  Look at AB-154/RC-292 Swivel Base with Base Plate on the web page I referenced above.  You'll need to adapt this to the fiberglass mast, but that's something you can do with PVC.  

Have fun, and let us know how it turns out!
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