[Lowfer] Not a RotoHammer, but a good pilot hole starter

[Stan, W1LE]

Hello Andy,

There are some limits to this process of using pressurized water to
wash away a small, but  deep,  hole to drive a ground rod into.

As the water does the drilling, the fines (very fine particles) of sand
and organic material are washed away, leaving larger stones with low 
conductivity
that will be touching the metallic ground rod.

In time, the hole around the ground rod will back fill with fines, but 
that may take years.

In other words the earth resistance between the ground rod and the earth 
will
be higher than normal, if pressurized water is used to wash away a hole.

If the ground rod is just driven into the ground, you will achieve the 
best possible ground rod to earth resistance.
If the ground rod to earth resistance still does not meet your 
requirements, add another at least the
length of the ground rod away from the first and bond them together with 
a low impedance wire or copper strap.
Continue adding ground rods until you achieve your objectives.

A BOSCH BRUTE electric impact hammer is one automated method to drive in 
ground rods without the water drilling.
The ground rod driving adapter is also needed, Check out your local Home 
Depot rental store.

Ground conditions and soil composition vary everywhere.
Some times a ground rod can not be driven vertically into the ground.
Look at alternative methods of achieving a low impedance ground.
Possibly a ground mat or ground radials on or just under the surface.

The only way I would use water drilling is to drill a larger hole, ~ 
4-6" diameter,
drop the ground rod into the hole, and back fill and tamper in Bentonite 
or coke breeze to
ensure the lowest possible ground rod to earth resistance.
Both of these compounds are no maintenance, unlike other temporary
  treatments like epsom salts or salt water.

Most ground rods are either a copper clad steel
or galvanized steel

I have seen some shorter ones that were a copper flash plated steel rod,
but that thin layer of copper gets abraded away with the impact of 
driving it in.
Once the steel is exposed, rust destroys the earth to ground rod 
conductivity,
and further erodes any remaining copper plating.

Who really checks their ground rod performance  after installation and 
periodically there ever after ?
(short answer, no one  !)   Ususaly maintenance is limited to inspecting 
stuff above ground.

Stan, W1LE       Cape Cod      FN41sr





On 11/5/2010 8:32 PM, Andy - KU4XR wrote:
> Having come to the conclusion that there has to be a " better way "
> or at least " another way "; I came up with this idea. I'm sure it's
> not original, but I can't remember seeing anyone ever post anything
> about this method of " hole drilling " before. Using a 4 foot piece
> of Brakeline, and my 3/8th inch B&D hand drill, along with a pitcher
> of water; I had a pilot hole if you will, drilled, and the Ground
> Rod instantly sunk 4 feet into the ground, in an hour-No Hammering !!
> Unfortunately, at the 6 foot deep level, the sound of the hammering
> went from " thunk-thunk-thunk " to a " ting-ting-ting " sound every
> swing, and the rod stopped moving...pretty soon, so did I.
> Here's a not too good quality picture of the Homemade Starter Hole
> Drill Bit:
>
> http://ku4xr.webs.com/apps/photos/photo?photoid=105349124
>
> 73 all:
>
>
> Andy - KU4XR - EM75xr - Friendsville, TN. USA
> LOWfer Beacon " XR " @ 185.29875 KHz
>
> **** Experimental QRSS-180 Transmissions ****
>
> Coordinates:  N:  35º 43' 54" - W:  84º 3' 16"
>
> http://www.myspace.com/beaconxr
>
> http://ku4xr.webs.com
>
> http://lwca.org/community/YaBB.pl
>
> *** The 5 most important words ever spoken ***
>
> http://ku4xr.webs.com/5mostimportantwords.htm
> ______________________________________________________________
> Lowfer mailing list
> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Lowfer at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>