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@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 telesc
ope 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@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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>
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