Ground rod question

Today, a friend called me who was doing a project. They had a copper coated steel rod about 5/8" dia. that was to be used as a ground rod for
electrical. They had no means of bending it, as it had to make a couple of three doglegs to get around concrete. I told him that heating it would melt the copper, and did not know if the inspector would pass it with the copper gone. He said that was what the inspector told him to do. We'll see. If it works, okay, if it doesn't, I'll set up a jig and bend it cold.
Now to the point. As I heated the copper, I noticed a beautiful color change. Like peacock colors. Would it be possible to dissolve copper into a solution, possibly using acid or electrolysis, then have the copper be deposited on metal sheeting so that it could be heated again to get the iridescent hues?
I've read a lot about electrolytic removal of rust, and it seems pretty straightforward. This would be (?) a two step process. I'm going to Google up on it. Anyone ever try it?
Steve
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Usually done right on the job with a 1/2" "hickey bender". That is a manual bender for 1/2" rigid conduit. Most construction electricians will have one on their truck somewhere.
Vaughn
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Saw a used one today at the pawn shop for $10. Is that a good price? Looked new.
Steve
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You would need a Solution 20-25% of Hydrofluoric acid (Nasty Stuff) 50% Nitric acid, and 20-40 Volt, 1 Amp power supply. Depending on time and current, you can get a nice copper coating on any surface. Google Hydrofluoric acid before you even try it. Not something you want to get on any part of your body. As Simon says, go with cold forming.
Jim
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SteveB wrote:

It is trivial to get a strike coating of copper on steel. Just put the steel into some copper sulfate (sulphate if you're British).
Grant
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On Wed, 30 Apr 2008 23:45:54 -0800, "SteveB"
-snip-

-snip-
Problem is the colors aren't permanent. Here's a thread on heat painting copper- [and attempts at preserving the colors] http://www.metalartistforum.com/forum/showthread.php?tid 4
And here's a Copper artist's site- http://coppercolorist.com /
Beautiful stuff-
Jim
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Why do you need copper plating? The electrical conduction through a steel rod is plenty for a ground, and a thin layer of copper on the surface isn;t going to make a significant difference.
Is it for preventing rust? Galvanizing would probably be better. I say just bend it. If you need heat, then you will damage the copper in those areas, but the thing will still make a usable ground which should last for years. You could paint the damaged parts with some zinc primer, or smear on some roofing cement.
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The copper clad can carry hundreds of amps when asked upon. The steel can't. Electrons flow on the skin. A clamp on the outside puts or gets electrons to or from the ground.
The ground is the important point that the electric company uses at your house.
When you have a power line hit and you have a protective circuit dump the garbage signal (noise) onto the ground line, you don't want it to float. Floating puts it on all of the other ground lines in the house. You save the PC on phase 1, but kill the Plasma TV on Phase 2 - both sharing the common line in the box and common ground connected to the common line.
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
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On Thu, 01 May 2008 20:42:06 -0500, "Martin H. Eastburn"

Just a quick question here. If the extremely thin electroplated coating on a steel ground rod will carry hundreds of amps, as you say, hows come my 250 amp welder has them big thick cables coming out the front, there?
Bruce-in-Bangkok (correct Address is bpaige125atgmaildotcom)
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wrote:

I think Martin is generalizing incorrectly about the skin effect, which applies only to high frequency AC. It's a phenomenon that becomes important at radio frequencies. At DC, or at low frequencies, conduction is uniform, or nearly so, across the whole section of a conductor.
Of course, copper has something like 10 times the conductivity of steel, so you have to take the thickness of the copper cladding into account, too.
-- Ed Huntress
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On Fri, 2 May 2008 02:38:13 -0400, "Ed Huntress"

Most of the copper coated ground rods I see are electroplated and the plating is maybe 0.0005 thick. I don't believe it carries much current.
Bruce-in-Bangkok (correct Address is bpaige125atgmaildotcom)
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Skin effect is important at 60 hz. too. I forget the exact figure but as I remember at 60 hz it is not worth making conductors over 4 inch in diameter.
Recently saw a house with lightning rods where the wire to ground was Litz wire.
Dan
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Actually Ed is not far off but missed himself.
Current density for all points on a cross section of A is j=i/A
However since the resistivity of material varies greatly, the current flows in the copper.
The skin is the thin plating on the steel rod that every house has pounded into the ground near the power meter.
What messes up the even density in a solid copper rod (we don't have) is that of the electromagnetic field that drives the current outward. So the real density is loaded at the outer edges and this process really takes place in massive form in RF.
TV's are fed by an antenna. The antenna is fed by a air core coax. The central wire is a tube. No reason for using copper that electrons won't go. This makes the coax a little more flexible.
28 cycles that was intended to be used on Navy ships - with large iron transformers acting as ballast actually tunnels to the center of the conductor. An arm placed across two power posts will have the marrow burnt out. The Navy aborted the experiments.
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
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On Fri, 02 May 2008 13:03:02 +0700, Bruce in Bangkok

That ground rod is only needed to carry that hundreds of amps for a split second*, until the breaker trips or the lighting strike is over.
*Or a few seconds as a worst case senerio.
Thank You, Randy
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If you have ever seen the results of an actual lightening strike you wouldn't be quite so casual about the amount of current the ground circuit is required to carry.
Now, if you are talking about "static grounds" as used on airfields or around fuel storage systems that is a totally different proposition.
Bruce-in-Bangkok (correct Address is bpaige125atgmaildotcom)
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wrote:

In my brain, a ground rod is for emergency path of current, and not a constant flow.
What do I win?
Am I right?
Steve
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On Fri, 2 May 2008 09:03:32 -0800, "SteveB"

The problem with the discussion is that there are a number of different types of "grounds". One, for example, the "static ground" is designed to dissipate static electricity to avoid igniting fuel during a re-fueling operation. It has been many years since I worked on that type of system but if I remember correctly the resistance can be in the 1,000's of ohms.
Then we have the grounds used with lightening rod systems that may be required to carry Mega, or Giga-amps of current.
Then there are the ground systems for radio antenna systems and grounds for safety (and maybe even grounds for grounds :-).
What kind of ground are we talking about.
Bruce-in-Bangkok (correct Address is bpaige125atgmaildotcom)
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wrote:

In my case, a ground rod required next to the incoming 500Amp (large building) electrical service.
Steve
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On Fri, 2 May 2008 20:28:31 -0800, "SteveB"

Just had a talk with an Australian "Sparky", a licensed professional electrician for probably 50 years. He tells me that according to Australian code the ground to any building entrance (I'm using U.S. terminology here) is the same size wire according to Australian code. He gave me the wire code but as it is not AWG or metric I have no idea what the actual size is, other then he said it was larger then normal wiring in the building.
Bruce-in-Bangkok (correct Address is bpaige125atgmaildotcom)
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Actually a voltage basis and not much current. Martin Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
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