superdog
I Need A Drink
Premium,MVM
join:2001-07-13
Lebanon, PA
| reply to PersComp
Re: low on budget middle of nowhere
Guys, To make a long story short?, If all You are doing is putting an omni at the top, a mast is a great way to do it and cheap. If You have to hang any type of directional antennas from it, and You have to align it, FORGET IT!. I ripped out a 40 footer for this reason. I tried doing all the dangerous things like setting a ladder against it etc. and using scaffolding, which was the only way to effectively get to the top safely. Erecting scaffolding was a MAJOR PITA!, so I did what I should have done in the first place, and installed a 80ft tower in it's place. Now all I have to do is climb and align and go home, making what was a 4 hr. job a 20 minute deal.;)
--
»www.wavecrazy.net Join WISPA today! »www.wispa.org/ |
|
John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
 ·CenturyLink
1 edit | reply to newbiewisp
Fascinating installation...especially with the 2" pipe!
But thanks for the pics. And the drawings. Great stuff. You are to be applauded for your persistence and initiative.
I did notice one thing, though. You have four guy wires on your mast. This is generally "frowned upon" since that particular configuration does not transfer the loads correctly. This is why you see towers with only three attachment points...
If the guys are "loose" then that is one thing. If they are tensioned then you MUST use only three points spaced 120* apart.
Otherwise, the whole thing WILL fall down...
--
A is A |
|
newbiewisp
join:2004-11-19
Montreal, QC
2 edits | reply to PersComp
If you put up 40'mast,what kind of tower is it?because in orde for you to pull that up by yourself..it's gotta be really light.The pipe that we used is a 2" GI pipe..used for underground water pipe...very heavy...more than 50lbs each.I took 5 people to pull this thing up. |
|
PersComp
Premium
join:2005-08-17
Cayce, SC
| said by newbiewisp  :If you put up 40'mast,what kind of tower is it?because in orde for you to pull that up by yourself..it's gotta be really light.The pipe that we used is a 2" GI pipe..used for underground water pipe...very heavy...more than 50lbs each.I took 5 people to pull this thing up. »www.tessco.com/products/displayH···ntPage=1
The 40' model on this page is what I have.... |
|
nwn
Premium
join:2004-03-05
Centerville, IN
| reply to John Galt
I am also concerned about how close the guys are to the base of the pole in some of the pictures. Isn't the rule of thumb 80% of the height. So, for a 40' mast, the guys need to be 32' from the base. If they are too vertical, i.e., too close to the base, it will fall down in a wind.
--
Scott |
|
newbiewisp
join:2004-11-19
Montreal, QC
2 edits | We dont have much of a choice..the roof is not 32' from the base  ..and John..yes it was hard to straighten a 4 mast tower...because if you pull so much on any side it bends.And we cannot overtighten the the one on the top because of the weight it might just collapse.So what we did is to do it by eye...we tighten one side then we look...if it's bending on the right we pull to the left,we achieved this by using A turnbuckle for every two guy wires |
|
newbiewisp
join:2004-11-19
Montreal, QC | reply to superdog
Hello superdog1 can u show us some pics of this scaffolding...is this same principle as the the one used in building renovation?i'm curious... |
|
superdog
I Need A Drink
Premium,MVM
join:2001-07-13
Lebanon, PA
| said by newbiewisp :is this same principle as the the one used in building renovation?i'm curious... Yes it is. I don't have it anymore, as I put up a tower in place of the mast. It was a real PITA erecting the scaffolding every time I had an issue, and it always seemed like nothing went wrong until midnight in February. It's a lot of fun being on a roof @ 3AM with a steady wind in below freezing temps.:(
--
»www.wavecrazy.net Join WISPA today! »www.wispa.org/ |
|
Believer
join:2002-07-04
Baltimore, MD | reply to newbiewisp
What were the problems you were having with directional antennas on the guyed mast? Wind blowing them out of alignment? |
|
superdog
I Need A Drink
Premium,MVM
join:2001-07-13
Lebanon, PA
| said by Believer :What were the problems you were having with directional antennas on the guyed mast? Wind blowing them out of alignment? Nope. Just getting to them period. The only way to align a directional antenna, especially on a PtP link, is to get up there with it. This is next to impossible with a mast, unless You do something dangerous like we used to and prop an extension ladder against it or use scaffolding, which takes 2 hours to erect just to spend 10 minutes mounting and aligning an antenna.
--
»www.wavecrazy.net Join WISPA today! »www.wispa.org/ |
|
Believer
join:2002-07-04
Baltimore, MD
| reply to newbiewisp
The reason I ask is that we are putting up a 2ft panel next week attached to a 40ft guyed mast. It's the subscriber end of a PtMP link at 7.5 miles so we weren't planning on having a lot of problems once it's up.
The bottom 7ft of the mast will be attached to a chimney and we were planning on rotating it at the bottom to align it. Since the mast easily spins inside the guy rings we didn't think it would be a problem. Once it's attached and tightened at the base, I wouldn't expect it to go out of alignment.
Anything we should look out for? |
|
superdog
I Need A Drink
Premium,MVM
join:2001-07-13
Lebanon, PA
| said by Believer :Anything we should look out for? Yep!, The up/down tilt adjustment?. You will have to "guesstimate" the right tilt. Depending on how high the gain is, this may be a PITA??
--
»www.wavecrazy.net Join WISPA today! »www.wispa.org/ |
|
newbiewisp
join:2004-11-19
Montreal, QC
4 edits | reply to John Galt
We are currently planning to build a 20 feet 1 1/2"diameter pipe tower(no guy wires) to put up on the hilltop similar to this picture...my question is...how far apart do we have to put the pipes to withstand a 120 miles/hr wind the load is very small only the access point and the antenna.Obviously the farther apart those thee legs the more stable and stronger it is...but is there a rule of thumb or calculation to achieve the strenght i need...i'm asking this because obviously the cost...the farther the legs apart the more steel bar i need to reinforced the pipes.The base is no problem it will be a concrete cement sorry if this is off topic.. thanks again.
--
One man's garbage is another man's treasure |
|
John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
·CenturyLink
| said by newbiewisp :We are currently planning to build a 20 feet 1-1/2"diameter pipe tower(no guy wires) to put up on the hilltop similar to this picture...my question is...how far apart do we have to put the pipes to withstand a 120 miles/hr wind the load is very small only the access point and the antenna.Obviously the farther apart those thee legs the more stable and stronger it is... Well, what you are asking is an "engineering question"...and I am not an engineer, at least not a mechanical engineer.
AND you are asking for 120 MPH...Haahahahaha!
I would suggest that the 1-1/2" pipes be 18" apart and built using a triangular lattice, similar to this:
»www.radiancorp.com/Catalog/T2/Mi···?Search=
I am not sure that you need build a tower such as this for 20 feet...it might be better to just use a guyed mast..it is only 20 feet.
--
A is A |
|
newbiewisp
join:2004-11-19
Montreal, QC
1 edit | I know 120mph but here some statistics.
»www.typhoon2000.ph/season04.htm
guy wire is out of the questions...land is not mine.we are just gonna rent about 3 square meter just for the tower to build on.The subject is off topic for this forum but since u guys have a lot of experience in building tower or erecting them i might just as well ask em'.
--
One man's garbage is another man's treasure |
|
John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
·CenturyLink
| said by newbiewisp :I know 120mph... I will stick with my answer above. Look at how other towers are built. The better ones use the strongest possible configuration...a triangle. Every part of them is a triangle. Use round cross members if you have a choice. They are stronger than flat members, generally speaking, and this will makes it lighter.
As long as your welding is good and clean...it will be strong. Accuracy in the construction is necessary also. The objective is to transfer the load to the base, and avoid torsional twisting. Any point where the load is not transferred...fails.
--
A is A |
|
lutful
Premium
join:2005-06-16
Ottawa, ON
·TekSavvy Solutions..
1 edit | reply to newbiewisp
Among all the humour, did you get your answer yet?
We have one such "RemoteAP" running continuously at the Camp Fortune ski hill in Gatineu since last Christmas. You can try it out sometime if you are in the Ottawa area.
we have installed all sorts of networks (including 45Mbps VSAT) that have survived category 5 hurricanes in the tropics. |
|
Believer
join:2002-07-04
Baltimore, MD
| reply to newbiewisp
Re: low on budget middle of nowhere
Finally got the 40' guyed mast up today. Two foot panel attached to an Alvarion VL SU. |
|
newbiewisp
join:2004-11-19
Montreal, QC | pretty pic nice!!! |
|
