[TheForge] RE: Permalac

[Steven Smith]

It sounds like what I saw that was different is the polymer coating. 
Thanks for explaining Jim.

Steve

James Binnion wrote:
>  They are typically either phosphoric acid or tannic acid. Converting 
> the rust to iron phosphate or iron tannate. Wetting agents (for 
> greater penetration into the rust) and solvents (to dissolve oil and 
> grease) are the other active ingredients.
>
> Some of them also include a polymer to encapsulate the converted rust 
> and coat the base metal leaveing a primer like coating that can be 
> painted directly over with compatible coatings.
>
>
> Jim
>
> On May 18, 2007, at 7:11 AM, Steven Smith wrote:
>
>> I'd like to better understand what the rust converters are doing. I 
>> used some once, maybe 10 years ago, on a car I was repairing (forlorn 
>> hope). Phosphoric acid will change red rust into black, but this is 
>> just one oxide form to the other. The converter changed red rust to a 
>> black, shiny stuff. There is more going on with the converter (at 
>> least what I used) than simple oxide conversion.
>>
>> Anyone have a clue about this?
>>
>> Steve
>>
>>