[TowerTalk] 80M 4 Square Array Material options

[Stan Stockton]

I looked in Yagi Stress at what I had described.  Should be good for about 58 MPH without guying.  Not good enough, and as I said should be guyed.

However, if you change the taper schedule to this it should be good for 70 MPH.  In some locations that might be good enough without any guy ropes.  I would guy it one time in my location to reduce the sway if nothing else.  This 70 foot vertical element weighs about 78 pounds with hardware.  It eliminates one of the 24 foot 3 inch X .125 wall tubes, using 6 feet on each element and adds smaller diameter tubing sizes of shorter lengths at the top.

> OD      WALL     EXPOSED Length      Socket Head Cap Screw Size
> 
> 3.5       .216        144
> 3.00     .125          60                          3/8 x 4 inch
> 2.75     .120          66                           3.8 x 3.5 inch
> 2.50     .120          66                           3/8 x 3.5 inch 
> 2.25     .120          66                           3/8 x 3 inch
> 2.00     .120          66                           3/8 x 3 inch
> 1.75     .120          66                           3/8 x 2.5 inch 
> 1.50     .120          32                           1/4 x 2.5 inch 
> 1.25     .058          18.                          #10 x 2 inch 
> 1.125   .058          32                          #8  x 1.75 inch
> 1.00     .058          32.                        #8 x 1.50 inch

   .875.  .058.         32                         #8 X 1.50 inch
   .750.  .058.         32.                        #8 X 1.50 inch
   .625.  .058.         32.                        #6 X 1.00 inch
   .500.  .058.         32.                         #6 X .75 inch
   .375.  .058.          Adjust                   #6 X .75 inch
                                   24-68 inches

This is exactly what I would do if I didn't already have 25G towers for verticals.

73... Stan, K5GO

> On Jan 29, 2016, at 9:22 AM, Stan Stockton <wa5rtg at gmail.com> wrote:
> 
> I know aluminum irrigation tubing has been used by many with success.  Personally, I don't like it beacuse the wall thickness is so thin.
> 
> This is just my suggestion:
> 
> Buy two 24 foot lengths of 3.5 inch schedule 40 6061-T6 from your local metals supplier.  Also buy two 24 foot lengths of 3 inch x .125 wall.  Cut those 4 pieces into 12 foot lengths so you have four of each size.  Use 3/8 inch stainless steel SOCKET HEAD CAP SCREWS and the Optibeam style of element fastening (larger hole on one side to allow head to clear one wall of larger OD tubing) to join those together for each element with 3 bolts for each.  With a 12 inch telescope you will have 23 feet ending with 3 inch x .125 wall.  Then for each element buy 6 foot lengths of every size DXE has of .120 wall tubing starting at 2.75 inch OD.  You will need four of each size except the 1.5 inch OD where you would just have 3 feet of that size for each vertical - so you need two six foot lengths of the 1.5 OD.  Use the same fastening method and telescope everything through the 1.50 inch OD by six inches with two bolts for each joint.  Then for the rest, starting with 1.25 inch telescope them by four inches and use bolt sizes shown below.  The 1.25 through 1 inch is just regular .058 wall also available from DXE.  The total length of this vertical will be about 70 feet.  
> 
> So the taper schedule for what I described is:
> 
> OD      WALL     EXPOSED Length      Socket Head Cap Screw Size
> 
> 3.5       .216        144
> 3.00     .125        132                           3/8 x 4 inch
> 2.75     .120          66                           3.8 x 3.5 inch
> 2.50     .120          66                           3/8 x 3.5 inch 
> 2.25     .120          66                           3/8 x 3 inch
> 2.00     .120          66                           3/8 x 3 inch
> 1.75     .120          66                           3/8 x 2.5 inch 
> 1.50     .120          32                           1/4 x 2.5 inch 
> 1.25     .058          68                           #10 x 2 inch 
> 1.125   .058          68                            #8  x 1.75 inch
> 1.00     .058          68                            #8 x 1.50 inch
> 
> Although it would free stand with probably a 40 MPH wind, I would guy it one time, maybe from the top of the 2 inch section.
> 
> I am just guessing the total cost will be well less than $1,500 for four verticals.  You will have to use a drill press and a V block to drill a bunch of holes and engineer the method to walk it up and have it insulated from ground.
> 
> 73...Stan, K5GO
> 
> 
> 
> 
>> On Wed, Jan 27, 2016 at 9:05 AM, Daniel Hileman <n9wx at hotmail.com> wrote:
>> Hi All,
>> 
>> I am looking for advice on material to use for an 80m 4 square. Looking for the cheapest way to build an 80m vertical.  I have looked at towers,used utility poles etc. (Utility poles look like the best option so far.) Curious what you guys use. I know that it may not be cheap, but I would like to do the verticals as cheaply as possible and looking for your input. I do not have 70' trees to hang a wire from (hihi) as I know this would be SUPER cheap. ;-) Like I said, I do not expect it to be free, but $1,800 for an 80m vertical from "Zero-five" antennas is crazy, and really dont want to spend $3,000++ on a 4 square! Looking at options! lol. I know it's alot of aluminum,etc.
>> 
>> 
>> 73,
>> Dan N9WX
>> 
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