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[KB2WVO]

what say you on a free stand 30ft rohn 25  ?  2 to 3 yards of concrete ?? 
winds can hit 50ish gust sometimes but not often/


use will be for wire. no yagis or verts.
might put a 10ft mast ontop also . not sure but puttin it out there also..

thanks for ideas hints tips tricks so on ..

[KG4RUL]

Per ROHN specs, a free standing 25G tower can go up to 40' - refer to specs for base requirements

[WB8PFZ]

That seems like a lot of concrete to support some wire antennas. Probably over kill.

[W9IQ]

what say you on a free stand 30ft rohn 25  ?  2 to 3 yards of concrete ?? 
winds can hit 50ish gust sometimes but not often/


use will be for wire. no yagis or verts.
might put a 10ft mast ontop also . not sure but puttin it out there also..

thanks for ideas hints tips tricks so on ..

I would consider a free standing aluminum tower for that application. You can comfortably walk the tower up from horizontal with two people.

- Glenn W9IQ

[N2SR]

Per ROHN specs, a free standing 25G tower can go up to 40' - refer to specs for base requirements

No they do not. 

Rohn specifies a maximum of 30 feet between guying levels, which technically means 30 feet of free standing tower. 

[KC4GHP]

You can go 20’ unsupported.
Since you aren’t loading the tower at the top with beam antennas and such, my opinion is the wind load at the top is minimal.
You could add a multi band vertical with no issues and I don’t think a trapped beam for 10-20-40 would be a big deal. There are charts to calculate the wind load so
I recommend you consult those.

As to the concrete, 2 CuFt is fine with your tower base 2ft into the concrete.
Good luck in the contest.
My credentials: Wind Zone 4 subject to flooding and hurricane surge the worst experienced being 5 feet.
House is on pilings anchored in 2 CuFt of concrete.

[VR2AX]

The base acts as a 'friction pile' depending on its profile.

[KB2WVO]

what say you on a free stand 30ft rohn 25  ?  2 to 3 yards of concrete ?? 
winds can hit 50ish gust sometimes but not often/


use will be for wire. no yagis or verts.
might put a 10ft mast ontop also . not sure but puttin it out there also..

thanks for ideas hints tips tricks so on ..

I would consider a free standing aluminum tower for that application. You can comfortably walk the tower up from horizontal with two people.

- Glenn W9IQ

would be awsome if the price was the same as the rohn25. that is free.. 70ft i have to take it down so the cost of crane to lift it and i take it sct by sct from bottom till can lean it over without crashin

[KL7CW]

Rohn 25 is very strong if installed according to Rohn specs.  I have felt very secure at over 100 feet working on these towers.  If your tower is not guyed a considerable base is required.  A guyed tower may require less concrete, check ROHN data.  You could possibly use orthagonal 40 and 80 meter dipoles as top guy wires on a 30 or 40 foot tower, with possibly less strengent base requirements. Check the ROHN data.  There are some good arguments for locating a tower away from your house or shack, however look into the possibility of putting the tower a few feet from a structure and bracketing it to the structure.  However, engineer the attachment to the structure, do not just lag it into the siding.  ROHN has specs, I believe on how high you can go with a solid attachment point instead of guy wires.  On my towers, I buried part of a section in the concrete base, then after a few days, just stacked additional sections to go to 40 and 60 feet on my guyed towers.  If you feel safe climbing and have perhaps 2 helpers it is easy to stack sections with a gin pole, or if you are young and strong even without the pole, however this is NOT recommended since things can go wrong without the gin pole.
    I have designed installations with antennas on top of modest height towers, like 40 feet.  It is true that the horizontal force tending to push a tower over from a modest antenna is small, however the torque at the bottom of a self supporting tower quickly becomes very significant, probably at least a few thousand foot pounds. Even a trap vertical on the top of a 30 or 40 foot self supporting tower will result in significant torque at the bottom of a self supporting tower. 
  Personally I like the idea of a good solid say 30 or 40 foot ROHN tower.  I still climb at 81 years old, and can hang various dipoles, from the top or even stack additional sections to extend the height many more.  Climbing is potentially very dangereous, requires hundreds of dollars of equipment and a few qualified helpers. Working on antenna crews, we needed to be re-certified every few years, which was at least a few day course where we practiced rescue techniques.  Remember if you call 911, your local fire department may not be able to rescue you if you become incapacited on top of your tower.
   Download and study the ROHN tower installation guide.  Also I believe ARRL has books on tower installation and safety.
                   Rick  KL7CW

[KB2WVO]

near house might be one of the towers.. my end game is a loop .. 2 towers for one side and trees for other. one of the towers is in the way back yard 80 so ft form house. 2nd tower . might put near house or attach.
i had asked this ? as i kind of like to stay away from guys. they would be in the way in the yard. for one of the towers. the other in the way back of the yard would be ok guyed but would be nice not to have to think of guys when walkin around lol

lots to think on ..

Rohn 25 is very strong if installed according to Rohn specs.  I have felt very secure at over 100 feet working on these towers.  If your tower is not guyed a considerable base is required.  A guyed tower may require less concrete, check ROHN data.  You could possibly use orthagonal 40 and 80 meter dipoles as top guy wires on a 30 or 40 foot tower, with possibly less strengent base requirements. Check the ROHN data.  There are some good arguments for locating a tower away from your house or shack, however look into the possibility of putting the tower a few feet from a structure and bracketing it to the structure.  However, engineer the attachment to the structure, do not just lag it into the siding.  ROHN has specs, I believe on how high you can go with a solid attachment point instead of guy wires.  On my towers, I buried part of a section in the concrete base, then after a few days, just stacked additional sections to go to 40 and 60 feet on my guyed towers.  If you feel safe climbing and have perhaps 2 helpers it is easy to stack sections with a gin pole, or if you are young and strong even without the pole, however this is NOT recommended since things can go wrong without the gin pole.
    I have designed installations with antennas on top of modest height towers, like 40 feet.  It is true that the horizontal force tending to push a tower over from a modest antenna is small, however the torque at the bottom of a self supporting tower quickly becomes very significant, probably at least a few thousand foot pounds. Even a trap vertical on the top of a 30 or 40 foot self supporting tower will result in significant torque at the bottom of a self supporting tower. 
  Personally I like the idea of a good solid say 30 or 40 foot ROHN tower.  I still climb at 81 years old, and can hang various dipoles, from the top or even stack additional sections to extend the height many more.  Climbing is potentially very dangereous, requires hundreds of dollars of equipment and a few qualified helpers. Working on antenna crews, we needed to be re-certified every few years, which was at least a few day course where we practiced rescue techniques.  Remember if you call 911, your local fire department may not be able to rescue you if you become incapacited on top of your tower.
   Download and study the ROHN tower installation guide.  Also I believe ARRL has books on tower installation and safety.
                   Rick  KL7CW

[KH6AQ]

[/quote]

would be awsome if the price was the same as the rohn25. that is free.. 70ft i have to take it down so the cost of crane to lift it and i take it sct by sct from bottom till can lean it over without crashin
[/quote]

How much will a crane cost? As Glenn says a self supporting aluminum tower is an option. Texas Towers sells the Universal Tower 4-30 for $529 plus shipping. It weighs in at 38 lbs.

Texas Towers   https://www.texastowers.com/towers/ss.htm   

[W4FID]

I think the base should be deep enough to be well below the frost line.

[N1UR]

I would strongly suggest that you go and help someone do a job that knows towers and learn a bit before tackling your first tower project.  People get hurt and sometimes die working on towers without any experience.

I personally will not climb a 30 foot Rohn 25G self supporting.  20 ft max then some king of guys, temporary or permanent.

Ed  N1UR

[K1FBI]

I would strongly suggest that you go and help someone do a job that knows towers and learn a bit before tackling your first tower project.  People get hurt and sometimes die working on towers without any experience.

I personally will not climb a 30 foot Rohn 25G self supporting.  20 ft max then some king of guys, temporary or permanent.

Ed  N1UR

I climbed 40 ft of unguyed Rohn 25G multiple times, with the tilt base no less. Three foot long threaded rods into the cement, so the bolts for the tilt mechanism are the weak point.
I don't recommend this, but if you had the non-tilt base and don't overload the tower with too much antenna there is no need to be extremely worried.
With 30 feet and the non-tilt base I wouldn't even give it a second thought.

[N2SR]

I climbed 40 ft of unguyed Rohn 25G multiple times, with the tilt base no less. Three foot long threaded rods into the cement, so the bolts for the tilt mechanism are the weak point.
I don't recommend this, but if you had the non-tilt base and don't overload the tower with too much antenna there is no need to be extremely worried.
With 30 feet and the non-tilt base I wouldn't even give it a second thought.

https://www.wmur.com/article/ham-radio-operator-killed-when-tower-he-was-dismantling-collapses/28570300

The men were harnessed to a section of tower more than 40 feet up when the tower collapsed.

The tower collapsed (actually fell over) because they removed the first (lowest) set of guys -  without adding temporary guys.  The tower owner used a tilt-over base, which is not designed to be a free standing base. 

There are bold tower climbers and there are old tower climbers, but there are no old, bold tower climbers.