Several people have e-mailed me, and asked for a re-cap since I received
some some of responses directly.
My original question was how to attach a 2" wide copper ribbon to a 5/8"
ground rod. Here are the replies:
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1. Get rid of any mushrooming from the driving process with a file.
2. Coat the top 2 inches of the rod with an active liquid or paste flux.
3. Form the end of the strip around a rod of smaller diameter than the
ground
rod, so that when it is splipped carefully over the ground rod, it will be
in
contact all around.
4. Heat the rod just below the strip with a propane torch until the rod and
strip come up to soldering temperature, then add solder, which will flow in
very
nicely by capilary action.
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Tom: there's no substitute for the soft-copper clamp from PolyPhaser. Unless
you're retired with lots of time on your hands, homebrewing makes for an
even more expensive clamp that probably won't work as well
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I purchased a ground rod connector that fit over the top of the
ground rod (with a nice setscrew for compression), and terminated
in a flat "tongue" with a hole for a second screw. I then simply
fastened the strap to the tongue with a bolt/washer/nut.
The connectors for the 5/8" rod are reasonably beefy, and you
can use a vise to bend the tongue to a convenient angle.
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Tom, if you "come down" onto the rod in linear fashion, fluting or
shaping the 2 inches around the well cleaned rod top and then use several
SS "worms" it should work well for you.
The circumference of a 5/8 rod is very nearly an exact 2 inches.
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I cut a slit in the 2" copper strap for the hose clamp to go through, than
wrapped my copper strap around the copper ground rod. Once wrapped, or
during the time I wrapped it, I put hose clamp through and tighened it. It
was hard to get the strap to bend into such a sharp turn, but I managed.
The finished connection appears good, I pulled on it and it held firmly. I
also coated the strap and rod with NoAlOx (sp?) prior to installation which
made the strap and hose clamp rather slippery to hold on to while
assembling.
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My recommendation is to do the right thing and use the Polyphaser
clamp. Don't use the 'cheap ham solution' - it won't be a reliable, longterm
solution anyway.
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I have in the past used brazing rod and an acectlyene torch to heat the
ground
rod sufficiently to weld the materials together. I am not sure if this
qualifies
for an acceptable connection or not.
I have found that local electricians have been willing to help me prepapre a
cable with compression type fittings. Industrial stores that sell battery
cables
will prepare a cable with very large wire and compression fittings. They
use a
hydralic press to collapse the fitting onto the cable. Not something an
individual can do. The ends of the cable then have eyelets that allow me to
bolt
it onto the tower leg with one end and to the 4 inch wide copper strap that
runs
from the tower base back to my home. I use another similiar cable on the
house
end to tie the ground distribution to the places it needs to go. One wire
goes
to the ground buss in the power panel, another wire comes down to my room
for the
ground for my equipment, and a third to the ground on the telephone tie
block. I
have tried to make them all single ended. Ground loops do strange things.
Thought I would add my experience to that of the group. People who make
battery
cables are a good source to make a cable up for a ground system. They have
the
fittings and very large copper cable and the press to put the compression
fittings on with.
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As I understand it, you are using a 4" braided copper strap to attach to
your ground rod. First, I would drive a 1" copper pipe X 8' deep and coil
the brade inside the copper pipe and solder it in place. You don't need a
clamp. You may need to use a small torch to solder the braid in place
because of the heat loss in the copper.
What ever you do, take some copper sulfate crystals and put them in a can
with a hole in it to let the copper leach into the ground. You might want
to drive your rod right through the center of a paint or coffee can.
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Thanks again for the suggestions,
Tom K3GM
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