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One method used to prevent rust, is to insulate the metal from moisture and oxygen by covering it with protective chemical layers or paint. This method is effective as long as the protective surface is not damaged, for example, stone chips, scratches, abrasions i ....

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.... or cracks on the vehicle, which is impractical. Another problem is that it is almost impossible to hold a charge (potential difference) on a sharp thin edge of metal, and so this technology is not really suited for vehicles, which are made up of many irregular shapes. Because of this, it is also ineffective on existing rust and the areas surrounding it, as rust always causes sharp edges and damaged paintwork. Electronic rust prevention is another method used to prevent rust using one of two technologies; either Impressed Current or Sacrificial Anode. Impressed Current units are extremely effective in dry conditions but ineffective in the wet. Sacrifi ....