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Electric rust prevention?

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Old 06-27-2006, 08:58 AM
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^ I agree. We need to test this...lol I'd spend the $100 if it DID work. Or I'd steal the system off my Sebring and put it on the Bonne
Old 06-27-2006, 10:48 AM
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Originally Posted by BillBoost37
Call it in Rob..

til then...I'm believing the ship/sub builder with years of experience in salt water.
The saltwater is the electrolyte between the anodes mounted on the hull and the hull of the ship. The interior of the ship is not protected. You have to have an anode and cathode in an electrolyte and the anode and cathode must be metallically connected to have a corrosion cell. If you take away any one of them you do not get corrosion. Electrons flow from the anode to the cathode through the metallic path. An oxidation reaction occurs at the anode in the electrolyte, thus it looses positive ions and in the case of steel it is Fe++. A reduction reaction takes place at the cathode. The electrons passed to it from the anode react to the electrolyte to change positive ions in the electrolyte to neutral ions. H+ goes to H2. (Think why lead acid batteries give off hydrogen gas). The anode is loosing material and the cathode does not. This is why all anodes must be replaced eventually. Here is a basic corrosion cell:


Here is a picture showing how one portion of a metal takes on the role of the anode and another takes on the role of the cathode. Ions are passed through an electrolyte. If there is no electrolyte ions can not flow so the anode you put on your car will not act as the anode to the car body unless there is electrolyte connecting it. Corrosion will still take place locally where an electrolyte is present.

But hey, my job is corrosion engineering and I have NACE certification so what would I know about this stuff anyway?
Old 06-27-2006, 12:38 PM
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Good stuff to know..

Ever wonder if there'* any areas we don't have experts in?

So the water works for the ship.. how can we make it work?
Old 06-27-2006, 01:53 PM
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I'm seriously considering getting one and testing it when I get an extra $100
Old 06-27-2006, 02:18 PM
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Just be careful the discharge does not start to affect the performance of the PCM/ECM.
Old 06-27-2006, 03:02 PM
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Originally Posted by ssei1995
Just be careful the discharge does not start to affect the performance of the PCM/ECM.
That was one reason why I was hesitant to get it put on my car, besides the heavy price tag. I was worried it would interfere/affect the car'* electronics. I was told that it would not harm anything.
Old 06-27-2006, 03:18 PM
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Both the engines oin my boats have cathodic protection using a piece of zinc . And the high pressure refined gas line that runs next to my bedroom window (ya I got the property cheap) has a cathodic charge to it and Sun oil warns not to put anything metal near it because of the charge in the pipe line will disintagrate iron or steel with a quickness. but I wonder how effective it would be on a car that can not be grounded because of the tires. If it does work why not just screw a piece of zinc on the frame and save yourself the money and electronics. I have heard that magnesium will work as well?
Old 06-27-2006, 05:06 PM
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The hot water heater in your house should have an anode in it as well. In fact, when the anode is depleted is when your tank will start to rust out real quick. All buried steel pipeline must be cathotically protected (charged as you say) as mandated by the DOT. Underground storage tanks, docks, some buildings...the list goes on for things that use this to combat corrosion.

Magnesium, Zinc and Aluminum are the most common anodes. These are used for "galvanic" protection. Metals can be ranked by how noble they are, or in other words how reactive. If you connect two different metals with a wire and put them in an electrolyte they will naturally have a measurable voltage difference between them (milli-volts) because of the difference in reactivity. The voltage difference is the "charge." If you get metals with a large enough difference and a good electrolyte you have a battery. In this electrochemical "cell" the metal that is less noble (more reactive) will corrode and the other, more nobel, metal will be "protected." The key is they will only do this when metallically connected and both are in a shared electrolyte. Only the parts of the metals in the electrolyte will react. Nothing will happen to the part of the metals that is out of the electrolyte. So if you just go sticking chunks of zinc or magnesium on your car it will be useless until both metals are submerged in an electrolyte.
Old 06-27-2006, 05:09 PM
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Originally Posted by Chinski
This will not work. You have to have an electrolyte between the anode and cathode. Air is not a good electrolyte. The only way I could see it working would be if the anodes were on the outside of the car and during a heavy rain the water made good contact between the anode and the steel. It would only protect areas within the continuous contact area. Steel with a single drop of water on it, and the water is not touching he anode, will not be protected.
The web site said "Included clear paint sealant (with highly conductive polymers)", my guess this is their way around this fact.

10 years on subs, and we just used zincs.
Old 06-27-2006, 05:36 PM
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There is a big difference between conduction of electricity and ionic flow. You have to have both a path for electrons to flow and a path for ions to flow. The only solid electrolytes that I am aware of are in the developmental stages for hydrogen fuel cells and even then they must be kept moist to allow ionic flow. There is one that NASA is working on that is solid and dry but it must be heated to something like 160 celcius to allow ionic flow.

Spend your $100 and do a scientific test on a couple pieces of metal hanging in the air. Let me know how it works out for you.

NACE writes the standards for corrosion control that EVERYONE uses. In the class I had, my NACE instructor said he bought a car with one of these systems (didn't know it came with it until later). His boss told him he would be fired if he did not get it removed. Would be like a top GM executive driving a Ford to work. Thats how much of a joke these things are in the corrosion industry.


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