[TowerTalk] 40M Homebrew Vertical - mounting ideas solicited

[David Robbins]

lets see if I can describe this... my 40m 4-square verticals are rohn pipe towers supported between two 2x4's about 5' up.  there are 2 bolts through the 2x4's and vertical that I insulate with fiberglass tube so you can pull one bolt and lay the vertical down.  this is a bit more than a one person job though because those verticals are pretty heavy.

 

an idea to do this now so it will work from 10' up might be something like this:

1. mount two plates at the top of your support mast sticking out one side about the thickness of your vertical's base and above the base by at least that much... these will be plates that the vertical will pivot on.

2. find round fiberglass that fits inside the bottom of your vertical sticking out probably 5' or so from the bottom of the tubing (grainger and other industrial supply places have assortments of fiberglass tubing and rod that would work for this)

3. clamp the fiberglass to the mast going through the two plates to simulate the raised position, draw a vertical line on the pivot plates at the center line of the fiberglass to show how far out from the mast to drill.  then pretend you are laying the vertical over and figure out how far above the top of the support mast you need the pivot hole to be for it to let the top of the vertical down so you can work on it... probably twice the thickness of the fiberglass, but don't cut it too close.

4. clamp the fiberglass back in the raised position, leave enough above the plates to go inside the vertical base and drill the pivot hole through the two plates and fiberglass... insert a good bolt with washers to let it pivot and keep it from moving sideways if the fiberglass is much smaller than the mast.

5. locate one or two places down the support mast and drill through the mast and fiberglass for bolts to hold the bottom of the fiberglass when the vertical is raised.

6. put the vertical on the fiberglass and drill a hole through to hold it in place and to connect the feed cable.

 

if your vertical isn't too heavy, and the fiberglass is long enough, and you are strong enough, and it isn't too windy, and you are lucky, you should be able to undo the bottom bolts on the fiberglass and tip over the vertical on the pivot bolt, maybe using a piece of rope on it so you aren't up a ladder trying to keep it from crashing down once it gets past your reach.

 


Jan 22, 2014 12:18:18 PM, larryb.w1dyj at verizon.net wrote:

Hi all,

I am building a homebrew 40M vertical with raised radials. (Yes, I have studied the N6LF and K3LC literature.) 

It will be sitting on a 10 foot metal mast. I am looking for ideas for mounting the driven element. I want to be able to tilt the vertical over without effecting the radials. Obviously, the radials and driven element must not be electrically connected to the mast or each other. The mounting method should not effect the radiation pattern -- implying that it cannot be fabricated out of metal. I also want to be able to raise the vertical myself without my XYL needing to help me. I plan on fabricating this myself, only purchasing raw materials. 

I am open to any weird ideas! Pictures are especially helpful. 

73 -- Larry -- W1DYJ

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