DIY Antenna Tower

[kingshootr]

I'm a fairly decent metal fabricating hobbyist, and have been doing some drawing and figuring (dangerous, I know...)

ANTENNA TOWER (27FT)
QTY	DESC	Unit Cost	Net Cost	Lbs	Weight (Lbs)
7	10.5FT x 1-3/8" Fence Rail	$22	$154	8	56
6	3/8" Rebar x 10ft	$7	$42	4	24
1	18" x 1/4" Steel Plate	$20	$20	24	24
6	Paint	$5	$30
2	4 x 4 x 10 PT Post	$25	$50
2	Post Cap	$0	$0	1	2
12	Quikcrete	$8	$96
1	Antenna (Sirio GP 3-E)	$60	$60	5	5
1	LR400 x 50ft	$150	$150	15	15
Misc	??		$100
			$702		126

This is a pretty complete parts list to build a 27ft triangular antenna tower to support a scanner antenna, and probably a GMRS antenna at some point.




This list includes the parts needed to build a tilt-up mechanism, as well as the coax. I threw in another $100 for miscellaneous stuff I probably forgot. The tower with antenna and coax would weigh 126Lbs (that's conservative, I rounded up on all the component weights.) These pictures give an idea on the dimensions and how I intend to do the zig zag structure.

I figure it'll have some growing room - not so much for any kind of ham stuff, but who knows what else the future might bring. So for $700 and sweat equity - I think it would work. I realize a Rohn is about the same cost - until you throw LTL freight into the total. Plus my $700 includes the tilt up, concrete, and coax, so I'll be money ahead. Plus it'll be a fun project. It won't be until next year when I retire, but I'm a planner.

Any and all thoughts, critiques, and suggestions are most welcome.

 

[jeepsandradios]

While its a great avenue to hone in skills you can grab tower section dirt cheap now used. I have at least 150' of Rohn 25 laying on the ground that I've gotten for hardly anything. Most of it was just "come get it". While 27' does not sound high in regards to wind loads I'd be worried about wind load on the fence rails. I've seen fence bent all to crap after a tree branch fell on it. Thats just my thoughts. Long ago I realized its normally easier and cheaper just to buy what I want than spend time building something that may or may not work.

 

[kingshootr]

You live in Phoenix? I can pick up!

Yes, I have my post alerts set up on Marketplace and Craigslist for towers. If something comes along for the same cost as to build it - I'm jumping all over it.

The triangulation of the design I was coming up with is pretty stout. It won't have to support one those giant ham radio antennas, just a scanner and a GMRS one - both with really minimal sail area.

Now, with all that being said, I just got the engineers drawings for the steel building the tower/mast will be near. Because of snow load and wind requirements - this thing is going to be a fortress.

I'm back to considering a telescopic mast bolted to one of the steel posts.

 

[PRMII]

Using the triangular run down the legs of the tower will significantly reinforce it. I've always guyed my towers, even the "self-supporting" ones. Just a little extra insurance. I've used treated 4"-5" by 10-12' posts. I dug down about 2-3' and set the post in. Since my soil was mostly Clay, I just refilled the hole around the post, and tamped it as filling. Never had an issue.
I've toyed with the idea of building a fold over from scratch, but never got around to it. Getting a bit long in the tooth now to fool with it...
I'd suggest looking at some various tower designs, and see what you like. Build off that design. On the other hand, check out some of the Swapfests as you'll find some used tower sections there pretty cheap.

 

[FKimble]

$700 for only 27 feet? Take a look at Penninger. Premium equipment at a premium price but for only 27 feet worth a look. Also the various pushup fiberglass. Last time I priced a 24ft long Aluminum 2in diameter pole/pipe it was MUCH cheaper. Are you planning on using the 3/8 rebar for the zig-zags down the sides? If so you are gonna need a lot more than your spec sheet list.

Frank

 

[kingshootr]

Brain cramp on the rebar count . I've sinced walked away from this idea as it would be serious overkill for the little that I need.

Probably going with. 20ft - 25ft post with two small scanner/CB antennas. When I hit the drawings back for the metal building - it's a bomb shelter. I'll be able to secure the post to the eave for stabilizing without worry of damage to either.

I appreciate all the information and related experiences. Love this place.

Edit: Wow, that 35ft tip over is a heck of a deal!