Electronic Rust Inhibitors

[trenchdog73]

Well I seen a commercial wich lead to an internet search that provided a number of different electronic rust inhibitors by different companys. Anyways my Question to u all is if anyone has actually used on of these or knows some one who has. They seem like they might be effective but I would like to get the skinny on them other then the onsite testimonials and testing.

[Thunderbucket]

Dont believe all that you see on TV or the internet,,,if there was such a thing as an electronic rust inhibitor then the Big three would be all over it like a cheap suit.
sounds like another snake oil product like them oil additives which are supposed to keep your engine running without oil,,,even though they neglect to take notice that a lack of hydraulic pressure in a motor would have catastrophic results.
This one should get the whacked award for 2005

[Henry Rifle]

There are electronic rust inhibitors. The process is called cathodic protection (CP). It's used in buildings, on underground storage tanks, on pipelines and on ships.

It's accomplished either by inducing an electrical current, or by providing a sacrifical metal (sacrificial anode) that is lower (more negative) in the electro-chemical series, and will corrode more rapidly than the metal being protected.

The British navy protected their copper-sheathed ships by connecting them to iron anodes. Steel tanks and pipelines are protected by attaching magnesium anodes.

Applications to cars are not feasible, though . . . unless you're protecting something like those Cadillacs buried nose-first in the desert. CP could protect those.

[Thunderbucket]

I was aware of the sacraficial anode use on ships, and boats,,,also on aircraft,,,,and to some degree on cars cooling systems,,,,but this technology,,,while pretty neat sounding,,,is just that,,,PRETTY NEAT,,,I personaly would not want my cars body electrified,,,,,i'd be scared outa my wits driving through a lightning storm.
It's a moot point anyhow,,,,,Until i see's it with me own two baby blues,,,,i wont believe it.

[76GMC1500]

We have a CAPAC on our ship, cathodic protection. It does not use a sacraficial anode. It uses platinum electrodes located in 6 locations on the hull of the ship to give it a slightly positive charge. Platinum is used because it is very resistant to errosion caused by electrons leaving its surface (it isn't sacrificial). The positive charge prevents electrons from leaving the surface of the metal hull under water. When electrons leave the surface, they carry little bits of metal with them and that is what causes the corrosion. Instead, electrons from the water enter the hull of the ship. Too much of a positive charge will actually cause a build up of crud on the hull because the electrons carry crud with them onto the hull. Electrons will move into the hull anywhere there is missing paint. When current travels through water it, the water breaks up into oxygen and hydrogen. The hydrogen sometimes will form a bubble on the exposed area and can keep water off of the hull, further protecting it.

Cathodic protection works any time you have a metal suspended in an electrolyte. A steel hull in salt water, rebar in concrete and damp soil, water moving through a steel pipe, etc... But, I don't believe it will have any effect on something in the air like a car. The top side of my school's ship still rusts real bad.

[Henry Rifle]

Yep, that's the impressed current method vice the sacrificial anode method. We used both on pipelines. Where the pipe is continuous, we used rectifiers to develop the proper potential difference.

What ship are you on?

[Don Shillady]

There is always a small voltage difference between different metals when they are in tight contact such as welding even if there is no solvent. Not only that but the voltage depends on temperature which is the principle behind thermocouples, but the voltage results in only very tiny amperage and requires amplification for thermometer use. This is used in electroplating as for example if you want a good result on chrome plating you have to polish the surface first and then plate a layer of Cu, then a layer of Ni and finally the top layer of Cr. The idea is that Cu will give electrons to Ni and the Ni will give electrons to the Cr so that the Cr will not become Cr+3 ions and gradually combine with oxygen to form an oxide and most corrosion of any metal in air is likely an oxide since Oxygen is the second most reactive element, being only less reactive than F. Hey our atmosphere is a pretty vicious place and maybe you recall that gasoline is not free but the oxygen required for combustion is free and readily available? Field-Effect-Transistors are also indirectly dependent on voltage differences between layers of different metals relative to a substrate like Si or Ge. Thus a liquid solvent is not necessary for a electromotive voltage as long as the different metals are are in direct contact. As far as rust inhibotors go passive layers of electroplating are the simplest examples so ordinary Cr plating is a common corrosion inhibitor. It is not obvious that the Cu/Ni/Cr layers prevent/slow corrosion but this has been established for the best Cr plating.

Don Shillady
Retired Scientist/teen rodder

[Thunderbucket]

If there are doodads out there that can prevent electron transfer( which is what need to happen) then the thing would have to run 24/7 365,,,,to do the job.
I would think you'd have to plug the car in every night to keep the unit running.
I do know how to De-Rust parts using washing soda, water, and a battery charger,,,but this other gizmo strikes me as a good intention,,but short on proof.