Hi Gary. Wow that sounds like an awesome vertical ! 3" is pretty darn
beefy. You and Rick (and others off line) have answered my question. I
mean, I could have even found tapering solutions starting out at 1" and
ending up at 3/8" and I wondered how that would stack up against a "fat
cigar" in the same wind <g>. As I explained to Rick after 40 something
years of doing EE stuff and no ME stuff the saying use it or loose it
sure holds true. TU es 73 !
Gedas, W8BYA
Gallery at http://w8bya.com
Light travels faster than sound....
This is why some people appear bright until you hear them speak.
On 1/1/2020 1:54 PM, Gary K9GS wrote:
Hello Gedas,As a point of reference I have a DX Engineering 80/40 meter vertical. It is ~57 ft high
with a big trap at 32' for 40m.It's 3" aluminum tapering to 1". I live on a big
ridge and have some pretty high winds at times. When I first put it up I thought I would need to
guy it. It turns out that it is not needed. I've watched during high winds and it doesn't move
very much. I attribute this to having a pretty low cross section/wind load.I would definitely go
with the larger diameter for strength especially since you're going to walk it up.Please let us
know how it turns out.73,Gary K9GS
-------- Original message --------From: Gedas <w8bya@mchsi.com> Date: 1/1/20 11:54 AM (GMT-06:00) To: TowerTalk@contesting.com Subject: Re: [TowerTalk] Which Vertical is More Robust ? Hi Rick es HNY !TU for that advice. I need to look up the weight of the heavier duty fence pipe. As these are going to be elevated verticals which I "pivot" into place by myself I need to look at what the total weight will be. I have about 8' of 6x6 set in the ground then use a wooden frame that cradles around
the 6x6 and pivots the verticals into place. Kinda hard to explain but it will put the feedpoint at around 10' off the ground, then of course the length of the vertical. So I should be able to walk it up into place. Will check it out TU.But let me ask my question again, is it better to go with a larger dia pipe (even if it has a greater wind load) or better to go with a smaller dia tubing with less wind load? Assuming the wall thickness is the same for all the members.Gedas, W8BYAGallery at
http://w8bya.comLight travels faster than sound....This is why some people appear bright until you hear them speak.On 1/1/2020 12:23 PM, Richard (Rick) Karlquist wrote:> Recommend that you consider chain link fence "top rail" instead> of EMT. Get the "1 7/8 inch" OD variety. It is the same> diameter as "1 1/2 inch" water pipe. It is actually intended> to be structural. There is also a "1 3/8 inch" OD variety than> you can
telescope. It is the same diameter as "1 inch"> water pipe.>> Rick N6RK>> On 1/1/2020 8:13 AM, Gedas wrote:>> HNY to all !>>>> I cannot think of a better time to start a new 40m phased vertical >> project then the dead of winter with snow on the ground (as usual I >> could not get to it during the summer or fall).>>>> Anyway, I have drawn up two possibilities for a pair of 33' self >> supporting verticals. Both start out with a
10' length of EMT but one >> choice starts out with a larger dia then the other before I switch >> over to tapering aluminum sections.>>>> A) Starts out with a 10' length of 1-1/4" EMT followed by tapering 5' >> sections of aluminum tubing (4' long exposed, 1' inside the previous >> lower section) until the very top length section which will be 3/4" >> OD dia. These will be standard DX engineering aluminum tubes.>>>> B) Starts out with a 10'
length of 1-1/2" EMT, then a 5' length of >> 1-1/4" dia of EMT (4' long exposed, 1' inside the previous section of >> EMT) then followed by tapering 5' sections of aluminum tubing as >> above. The only difference being this choice would end up using 1" >> aluminum tubing as the very top piece.>>>> So the obvious difference between the two are that choice A) uses >> just one length of thinner EMT and overall thinner aluminum tubing >> sections to
the top while choice B) uses 2 lengths of larger dia EMT >> and then larger dia aluminum tubing to the very top.>>>> I do not have the software to analyze choice A) vs. choice B) in a >> high wind situation. I am uncertain if the stronger, larger dia >> tubing with it's higher wind load will be a plus or a minus in the >> end to it's overall strength. Any thoughts or comments on which one >> will survive better during heavy wind conditions? TU>>>> Gedas,
W8BYA>>>> Gallery at http://w8bya.com>> Light travels faster than sound....>> This is why some people appear bright until you hear them speak.>>>> _______________________________________________>>>>>>>> _______________________________________________>> TowerTalk mailing list>> TowerTalk@contesting.com>>
http://lists.contesting.com/mailman/listinfo/towertalk>>______________________________________________________________________________________________TowerTalk mailing listTowerTalk@contesting.comhttp://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|