Hi Gang,

I'm building my first 6 meter vertical antenna
for repeater use. I already have a 6 meter beam
for SSB DX use. (Cushcraft 5 element)

I'm using the plans from G3JVL for a 5/8 wave
aluminum antenna. I have the tubing from Texas
Towers (extruded aluminum) designed to fit in
to each other, so this should make a perfect
antenna when I get it cut to size. For those
not familiar with the G3JVL antenna, here is
a link:

http://www.hamuniverse.com/6metervertical.html

The advice I need is how should I protect the
antenna prior to putting it on the roof? Is there
a spray I should use to resist rust, or something
I should use when I connect the sections to help
maintain a good connection and prevent oxidation?
I suppose this might have the added benefit of making
the antenna easier to disassemble.

I was planning on using stainless hardware to assemble
the sections. I was initially thinking of using a
stainless hose clamp, but I was advised to drill a hole
through the sections and use a bolt and nut as that is
more reliable.

This is my fist shot at a homebrew, so any advice is
appreciated.

Thanks,

Mike N2QAC

pinpassion wrote:
Hi Gang,

I'm building my first 6 meter vertical antenna
for repeater use. I already have a 6 meter beam
for SSB DX use. (Cushcraft 5 element)

I'm using the plans from G3JVL for a 5/8 wave
aluminum antenna. I have the tubing from Texas
Towers (extruded aluminum) designed to fit in
to each other, so this should make a perfect
antenna when I get it cut to size. For those
not familiar with the G3JVL antenna, here is
a link:

http://www.hamuniverse.com/6metervertical.html

The advice I need is how should I protect the
antenna prior to putting it on the roof? Is there
a spray I should use to resist rust, or something
I should use when I connect the sections to help
maintain a good connection and prevent oxidation?
I suppose this might have the added benefit of making
the antenna easier to disassemble.

I was planning on using stainless hardware to assemble
the sections. I was initially thinking of using a
stainless hose clamp, but I was advised to drill a hole
through the sections and use a bolt and nut as that is
more reliable.

This is my fist shot at a homebrew, so any advice is
appreciated.

Thanks,

Mike N2QAC

Mike;

The first advice to protect your new antenna prior to mounting it is to
insure that nothing is allowed to fall on or against it while it is in
your shop. This is very detrimental to the final look of the antenna.
;^). Seriously though being made of aluminum it will not rust. It will
lightly oxidize but this is a natural action as aluminum is very
reactive with oxygen. If you are in a salty environment you might
lightly spay paint the aluminum with either a color paint or a clear
finish otherwise you really do not have to worry about the metal. Just
be sure that your paint does not have any metal in it.
One thing you might want to consider is coating the joints between two
pieces of metal with a conductive grease. You should be able to find
that at a Radio Shack or other electrical supply house. Using a nut and
bolt to hold sections of tubing together is a very good idea, just be
careful when tightening the nut not to crush the tubing.

Good luck;

Dave WD9BDZ

"pinpassion" wrote in message
oups.com...
Hi Gang,

I'm building my first 6 meter vertical antenna
for repeater use. I already have a 6 meter beam
for SSB DX use. (Cushcraft 5 element)

I'm using the plans from G3JVL for a 5/8 wave
aluminum antenna. I have the tubing from Texas
Towers (extruded aluminum) designed to fit in
to each other, so this should make a perfect
antenna when I get it cut to size. For those
not familiar with the G3JVL antenna, here is
a link:

http://www.hamuniverse.com/6metervertical.html

The advice I need is how should I protect the
antenna prior to putting it on the roof? Is there
a spray I should use to resist rust, or something
I should use when I connect the sections to help
maintain a good connection and prevent oxidation?
I suppose this might have the added benefit of making
the antenna easier to disassemble.

I was planning on using stainless hardware to assemble
the sections. I was initially thinking of using a
stainless hose clamp, but I was advised to drill a hole
through the sections and use a bolt and nut as that is
more reliable.

This is my fist shot at a homebrew, so any advice is
appreciated.

Thanks,

Mike N2QAC

Look at the way the Beam is heald together and use that method. The split
ends and the SS hose clamps. Use AL or SS for everything you can. If you
want to you can shine up the elements where they mate and use some pentrox
on them you can get from an electrical supply place. Maybe evens Lowes.

Mike:

One thing that no one will tell you is why manufacturers use plated hardware
which rusts instead of stainless. Cost? No. Stainless will not stay tight,
while plated hardware will rust up and then never loosen. So, if you use
stainless, it is highly desirable to use Nylon insert locknuts or else
carefully double nut everything, and add Loctite before assembly. It is no
fun finding another piece of the antenna at the bottom of the tower every
day after the wind blows a while.

--
Crazy George

On Wed, 7 Sep 2005 22:02:12 -0500, wrote:

Mike:

One thing that no one will tell you is why manufacturers use plated hardware
which rusts instead of stainless. Cost? No. Stainless will not stay tight,
while plated hardware will rust up and then never loosen. So, if you use
stainless, it is highly desirable to use Nylon insert locknuts or else
carefully double nut everything, and add Loctite before assembly. It is no
fun finding another piece of the antenna at the bottom of the tower every
day after the wind blows a while.

George, I wonder if you tried lubricating the ss parts before
assembly.

Stainess threaded parts are well known for galling, and can bind
before properly tensioning the fastener. It is a widely debated topic,
but common advice is to lubricate the parts. Google for debate on what
to use (wax, WD40, grease, moly etc)

My experience is that stainless threads should be lubricated whenever
used with nyloc nuts to reduce heat damage and galling of the nyloc
insert. Marine grease seems to work fine, and it doesn't seem to
unduly upset the prevailing torgue characteristics.

Mike, ss hoseclamps on telescoping tubes with split ends seems to work
fine. Put a bit of marine grease on the worm in the hoseclamp. I think
you are less likely to crush the tube than through-bolting it.
Remember that the joint is going to flex to some extent. A little bit
of corrosion inhibitor in the slip joint will help maintain a good
connnection through life... depends on the environment as to the
necessity to to this.

FWIW.

Owen
--

Dave, Ralph, George, and Owen

Thank you for your help and suggestions.

Mike

pinpassion wrote:
Dave, Ralph, George, and Owen

Thank you for your help and suggestions.

Mike

Thank You Mike. That's what we are here for.

Dave WD9BDZ

Stainless also has a passivated [read higher resistivity] surface.
Poorer RF conductor.

wrote:

Mike:

One thing that no one will tell you is why manufacturers use plated hardware
which rusts instead of stainless. Cost? No. Stainless will not stay tight,
while plated hardware will rust up and then never loosen. So, if you use
stainless, it is highly desirable to use Nylon insert locknuts or else
carefully double nut everything, and add Loctite before assembly. It is no
fun finding another piece of the antenna at the bottom of the tower every
day after the wind blows a while.

--
Crazy George

Owen:

We've had this discussion before, and I must be using better quality
stainless hardware than you have used. In the dozens of pounds of stainless
from 0-80 up to 5/8" I have installed in the last 40 years, I could not
specify when the last one galled if I had to. And I take lots of them
apart, in addition to those which I expect to last forever. OTOH, somewhere
around 40 years ago when I first started using stainless, I found plenty of
it on the ground under a month old installation until I wised up about the
fact that lock washers, even split ring style, were not enough to hold under
constant vibration. And especially so on tubing where the tubing collapses
before the lockwasher will bite into the nut.

--
Crazy George
"Owen Duffy" wrote in message
...
On Wed, 7 Sep 2005 22:02:12 -0500, wrote:

Mike:

One thing that no one will tell you is why manufacturers use plated
hardware
which rusts instead of stainless. Cost? No. Stainless will not stay
tight,
while plated hardware will rust up and then never loosen. So, if you use
stainless, it is highly desirable to use Nylon insert locknuts or else
carefully double nut everything, and add Loctite before assembly. It is
no
fun finding another piece of the antenna at the bottom of the tower every
day after the wind blows a while.

George, I wonder if you tried lubricating the ss parts before
assembly.

Stainess threaded parts are well known for galling, and can bind
before properly tensioning the fastener. It is a widely debated topic,
but common advice is to lubricate the parts. Google for debate on what
to use (wax, WD40, grease, moly etc)

My experience is that stainless threads should be lubricated whenever
used with nyloc nuts to reduce heat damage and galling of the nyloc
insert. Marine grease seems to work fine, and it doesn't seem to
unduly upset the prevailing torgue characteristics.

Mike, ss hoseclamps on telescoping tubes with split ends seems to work
fine. Put a bit of marine grease on the worm in the hoseclamp. I think
you are less likely to crush the tube than through-bolting it.
Remember that the joint is going to flex to some extent. A little bit
of corrosion inhibitor in the slip joint will help maintain a good
connnection through life... depends on the environment as to the
necessity to to this.

FWIW.

Owen
--