How to pound ground rods into earth? (San Antonio, Boerne: rental, Home Depot)

[alphabravo]

Hi all,

I moved from the DFW area where driving a ground rod into earth was not easy, but could be done with a sledge or post driver.

I now live in the Boerne area and have attempted to drive a 4 foot copper ground rod in with both sledge and post driver. Not having much luck with all the rock in ground.

What would be a better tool to use in this area? I thought about a hammer drill or earth auger but not sure if they would bust through the rock.

Thoughts??

AlphaBravo

[wCat]

Originally Posted by alphabravo

Hi all,

I moved from the DFW area where driving a ground rod into earth was not easy, but could be done with a sledge or post driver.

I now live in the Boerne area and have attempted to drive a 4 foot copper ground rod in with both sledge and post driver. Not having much luck with all the rock in ground.

What would be a better tool to use in this area? I thought about a hammer drill or earth auger but not sure if they would bust through the rock.

Thoughts??

AlphaBravo

Yes...you're trying to hammer into solid limestone. You definitely need some power tools. Check out Home Depot or Lowes to see what you could rent. We dealt with that on one of our properties. I wan't involved in the actual drilling, but I think they had to drill the hole a little bigger and fill around it with cement. Be sure to have your level handy if you go that route.

[SnappyBob]

Four foot sounds kind of short. The last time I had to put in a ground rod the reg's said 8 ft I think. I know we started out on a ladder. Is this for grounding a residence or some other application? This was about 3 years ago and was in San Antonio. Your mileage may vary. If I'm not mistaken you can also bury them horizontally in the ground. I believe it may have more to do with surface area of ground than just depth.

Note: Never put too much faith in electrical construction advise from someone on Internet forum. Especially someone named SnappyBob.

[alphabravo]

Thanks guys for the info.

The ground rod(s) is for a ham radio ground setup and not residence. I was going to drive multiple ground rods of 3-4 feet in length into the ground and tie them all together per an idea I saw online for rocky soils.

But, I also took SnappyBob's info and checked info online about the idea of laying the 8 foot rod horizontally for surface area. Looks like I still have to dig down about 2 feet and lay the rod, but that may be best way.

FYI, I did call the local rental place and they suggested using a rock drill/air compressor setup which is probably what wCat saw being used. Price was a bit steep to rent and so, I'll try the horizontal setup!

[satx56]

Think I'd try to keep it vertical. Laying it horizontal just might affect your signal or it's orientation. Probably not though I'm just thinking out loud. 6 or 8 foot is the length of the last one i got. Wcat is right unless they make like a small version of a fence post hammer. A cylinder just a bit larger than pipe to be hammered. It has a weighted end and handles on the side. But, I've dealt with the rock in the nearby hill country . We had a jack hammer for fence posts main braces or larger posts anyhow!!

[JohnCan2]

electrical code book says lay rod horizontally 2' depth.

[SnappyBob]

Does it have to be a rod? I was just thinking. If it really is just a certain amount of surface area in contack with earth. Why not get a piece of copper with the same surface area like a copper plate. If my math is right a 9 inch X 9 inch x 1/4 inch plate would give you the same surface area of a 1/2 inch diameter by 8 ft ground rod and then some not ever counting the sides. This would reauire a much smaller hole. I'll bet it would be pretty expensive though.

[satx56]

Originally Posted by SnappyBob

Does it have to be a rod? I was just thinking. If it really is just a certain amount of surface area in contack with earth. Why not get a piece of copper with the same surface area like a copper plate. If my math is right a 9 inch X 9 inch x 1/4 inch plate would give you the same surface area of a 1/2 inch diameter by 8 ft ground rod and then some not ever counting the sides. This would reauire a much smaller hole. I'll bet it would be pretty expensive though.

Or 1/2 " or larger ridgid or even flexible rolled copper tubing which is solid copper. Ground rods are just copper plated steel. This would be for horizontal application of course. Copper prices have probably fallen enough to make it feasible.

[Dopo]

Here's what I can tell you...
Look at 250.50 through 250.70 in the NEC book, especially 250.53.G

On this page, 250.53.G is quoted
http://www.lni.wa.gov/TradesLicensin...ts/Elc0607.pdf

Here's another page where you can read about the sections I told you
Grounding vs Bonding - Part 6 of 12

[alphabravo]

Thanks Guys for all the info. The "grounding vs bonding" url was very good! I also liked the idea of laying the 1/2 inch copper tubing horizontally. On to the digging part.... ;>(