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W5GA
09-01-2010, 05:29 PM
Does anybody have a magic trick for getting the last 2 - 2 1/2 feet of a ground rod in the ground? I've been using a T-post driver, and that's how much is left above ground when the driver is down as far as it will go.

NQ6U
09-01-2010, 05:31 PM
This always works for me...

http://static.howstuffworks.com/gif/dynamite-sam.jpg

KG4CGC
09-01-2010, 05:35 PM
I've seen those extendable, two piece drill bits (holder?) Snap together about every three feet. But I guess you would have to use something like that before you went to pounding there. (stx)

W5GA
09-01-2010, 05:38 PM
This always works for me...
http://static.howstuffworks.com/gif/dynamite-sam.jpg
With the California hard pan, it's the only way you get any of it in the ground!

NQ6U
09-01-2010, 05:56 PM
With the California hard pan, it's the only way you get any of it in the ground!

You got that right. The soil around here is about 2 feet (that's .6 m to you, Cor) of hard adobe clay atop a strata of boulders that vary from a couple of inches to a couple of feet across. I gave up on ground rods and ground to a cold water pipe even though it's not as good.

WA4TM
09-01-2010, 06:16 PM
I use one of these with a bit made just for driving ground rods.... http://www.milwaukeetool.com/CatalogItem/Images/28324_5340-21.jpg



Edit: Damn that was sure a wimpy picture but you get the idea.... (It's a demolition/hammer drill....)

K7SGJ
09-01-2010, 06:28 PM
I use one of these with a bit made just for driving ground rods.... http://www.milwaukeetool.com/CatalogItem/Images/28324_5340-21.jpg



Edit: Damn that was sure a wimpy picture but you get the idea....

Out here, after a few inches of clay, you hit caliche for about a foot or so. It's just a little harder than reinforced concrete. I, too, use a jack hammer for digging and for putting ground rods and fence T posts in the ground. I have bent many T posts trying to drive them in to this stuff. In fact, this is the 2nd one I've owned, and it is getting ready to go south, also. If I didn't have one of these things, I'd have to move or quit digging.

KG4CGC
09-01-2010, 07:51 PM
So, a long drilling bit is out of the question?

K7SGJ
09-01-2010, 08:37 PM
Don't know about the kind of ground GA has, but I've tried drilling, too. I welded a 4' chunk of steel rod onto a 2 inch masonary bit, turned down to a 3/4 inch shank. I put the bit into a 1" high torque industrial electric drill motor. After about a 6 inches or so, the bit seized up in the ground. The damn drill motor twisted me around like a rag doll. In the process, the ac cord wrapped around my hands which were on the handle of the drill, and of course the trigger. Needlees to say, I was fucked. If it wasn't for the fact I finally ran out of extension cord, I'd probably still be out there doing the 360 Oh Shit.

KC2UGV
09-01-2010, 08:43 PM
Don't know about the kind of ground GA has, but I've tried drilling, too. I welded a 4' chunk of steel rod onto a 2 inch masonary bit, turned down to a 3/4 inch shank. I put the bit into a 1" high torque industrial electric drill motor. After about a 6 inches or so, the bit seized up in the ground. The damn drill motor twisted me around like a rag doll. In the process, the ac cord wrapped around my hands which were on the handle of the drill, and of course the trigger. Needlees to say, I was fucked. If it wasn't for the fact I finally ran out of extension cord, I'd probably still be out there doing the 360 Oh Shit.

Ok, sorry man, I'm sure it really sucked, but your description of it has me rotfl'ing

"I'd probably still be out there doing the 360 oh shit"

rotfl

W5GA
09-01-2010, 09:58 PM
Don't know about the kind of ground GA has, but I've tried drilling, too. I welded a 4' chunk of steel rod onto a 2 inch masonary bit, turned down to a 3/4 inch shank. I put the bit into a 1" high torque industrial electric drill motor. After about a 6 inches or so, the bit seized up in the ground. The damn drill motor twisted me around like a rag doll. In the process, the ac cord wrapped around my hands which were on the handle of the drill, and of course the trigger. Needlees to say, I was fucked. If it wasn't for the fact I finally ran out of extension cord, I'd probably still be out there doing the 360 Oh Shit.
Now THAT is funny!!!
Talk about an "Oh no" second! I've got arms enough to stop a 3/4" drill in its tracks, but I don't know about a 1".

For those not familiar with the "Oh No" second....it comes from the famous "OH NO" bird. His scrotum hangs below his feet. When landing, all you hear is "OH NO, OH NO".

W5GA
09-01-2010, 10:01 PM
So, a long drilling bit is out of the question?
Actually, it is. Ground rods need all the contact with undisturbed soil they can get. That's why I use the T post driver.

W5GA
09-01-2010, 10:11 PM
You got that right. The soil around here is about 2 feet (that's .6 m to you, Cor) of hard adobe clay atop a strata of boulders that vary from a couple of inches to a couple of feet across. I gave up on ground rods and ground to a cold water pipe even though it's not as good.
Where in Lemon Grove are you? Years ago ('78ish) my oldest brother and I had stacked 5L monobanders @ 65' just off 94...Tooley St. Damn near got DXCC as a Novice with that setup. Turned it all with a Ham M and a home brew brake delay.

NQ6U
09-01-2010, 10:22 PM
Where in Lemon Grove are you? Years ago ('78ish) my oldest brother and I had stacked 5L monobanders @ 65' just off 94...Tooley St. Damn near got DXCC as a Novice with that setup. Turned it all with a Ham M and a home brew brake delay.

I'm on all the way over on the other end of town from Tooley St., about 2 blocks east of Lemon Grove Blvd. If you remember where Lemon Grove Middle School is, I'm just up the street from there.

PA5COR
09-02-2010, 04:45 AM
I have the benefit of living on young sea clay salty and soft and a very good HF ground.

For a safety ground you need to go deep, depending on how deep the first layer of permanent groundwater table is, ask a electrician in your town, they know, have it megged after you put it in place..
If your underground is rocky, putting in copper in trenches as deep as it will go, but then plenty of it...


For H.F ground you can put radials over , on, or in the ground.
Try ON4UN book, low band dxing ;)
I just buried 1800 feet of copper wire in the ground, laying on the ground and some wires are 6 feet up running over the fence.

That all for the 160 meter vertical L antenna....
I have 17 extra copper 7 feet and 10 feet long copper pipes driven in the ground on strategic points which are connected to the HF ground grid.
When the ground is hard, use copper pipe, hammer one end almost close put the water hose to the other end, and slowly with the water stream on,
push the narrow end with the waterjet in the ground.
dig up a 1 foot by 1 foot and 1 foot deep hole before you do that, after the rod is in place use bentonite or rock salt to fill the hole, both will spend salt along the rod for years to come, and improve the ground.

After 4 - 5 years replenish the bentonite or rock salt, bentonite can be found in some cat litter material, look on the bag, it will give the material it is made off.
Rock salt i get here for agricultural shops, used as licking stones for cattle.

Hope that helps...

W5GA
09-02-2010, 07:07 AM
I have the benefit of living on young sea clay salty and soft and a very good HF ground.

For a safety ground you need to go deep, depending on how deep the first layer of permanent groundwater table is, ask a electrician in your town, they know, have it megged after you put it in place..
If your underground is rocky, putting in copper in trenches as deep as it will go, but then plenty of it...


For H.F ground you can put radials over , on, or in the ground.
Try ON4UN book, low band dxing ;)
I just buried 1800 feet of copper wire in the ground, laying on the ground and some wires are 6 feet up running over the fence.

That all for the 160 meter vertical L antenna....
I have 17 extra copper 7 feet and 10 feet long copper pipes driven in the ground on strategic points which are connected to the HF ground grid.
When the ground is hard, use copper pipe, hammer one end almost close put the water hose to the other end, and slowly with the water stream on,
push the narrow end with the waterjet in the ground.
dig up a 1 foot by 1 foot and 1 foot deep hole before you do that, after the rod is in place use bentonite or rock salt to fill the hole, both will spend salt along the rod for years to come, and improve the ground.

After 4 - 5 years replenish the bentonite or rock salt, bentonite can be found in some cat litter material, look on the bag, it will give the material it is made off.
Rock salt i get here for agricultural shops, used as licking stones for cattle.

Hope that helps...
Thanks, Cor. I'm doing mulitple rods for a tower install. Being in an extremely lightning active area, I need several of them. The soil here makes this a great place for vertical antennas, but i'm not going there just yet. Tower #2 will be a 1/4 wave on 160.

PA5COR
09-02-2010, 08:45 AM
Ah, the luxury of having a 1/4 wave tower/antenna for 160....
I'in a street, row of houses, people are used to big antenna's here by now, but there is always a thin line...
The vertical L will be strengthened and will go up to 23 meters, the rest sloping down to 8 meters above ground.
ON4UN book, as well the ARRL and RSGB antenna books, as ARRL handbook have lots of material on this, also on the net you can find good stuff.

http://wadsworthsales.com/Documents/HARGER%20LIGHTNING%20PROTECTION%202008.pdf
http://www.lbagroup.com/international/tower-lightning-protection.php

W5GA
09-02-2010, 06:55 PM
Ah, the luxury of having a 1/4 wave tower/antenna for 160....
I'in a street, row of houses, people are used to big antenna's here by now, but there is always a thin line...
The vertical L will be strengthened and will go up to 23 meters, the rest sloping down to 8 meters above ground.
ON4UN book, as well the ARRL and RSGB antenna books, as ARRL handbook have lots of material on this, also on the net you can find good stuff.

http://wadsworthsales.com/Documents/HARGER%20LIGHTNING%20PROTECTION%202008.pdf
http://www.lbagroup.com/international/tower-lightning-protection.php
GREAT information, many thanks! But none of it tells how to get the last couple feet of ground rod into the ground. I may try the electric jack hammer route.

PA5COR
09-03-2010, 05:32 AM
Normally i use an oversized steeel pipe that just fits over the rod to be pounded in the ground, welded shut on one end with a nut, about 6 inches long, put that ovr the rod and use that to hit it with the hammer.
The rod will not bend that fast, and the end of the rod will be less damaged.
6 Inches above the ground gives you nough space to put a large clamp on it to get the thick wires connected to the rod through the clamp.
The jackhammer might work as well.

ab1ga
09-04-2010, 08:36 PM
GREAT information, many thanks! But none of it tells how to get the last couple feet of ground rod into the ground. I may try the electric jack hammer route.

Don't bother. You just "lay over" the protruding part of the ground rod in a trench and put in a new one nearby (spacing equal to the length of the rod in the soil, but according to NEC no closer than six feet, check code for possible exceptions) Or just cut the rod and carry on to the next one.