What is best for light surface rust

[Frodge]

What is best to paint on light surface rust on backside of fenders

[Matt Wilson]

I've had excellent results with Duplicolor Rust Fix. I prefer it over the other brands because it sprays on clear and turns black once the chemical reaction is done. It's tannic acid and turns Iron Oxide into iron ferric tannate to stabilize and seal up the material. Then you can primer (epoxy or etching) and paint over - and for a fender, then you could undercoat or do some sort of heavy truck bed coating or something if you are going to added protection for a driver car...
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1972 Standard Beetle
1969 Baja Beetle

[Frodge]

It’s really tiny spots on the inderside. Nothing major. Do they sell brush on?

[Kiper]

Do you have a local auto paint store in your area?. There are several liquid rust convertors on the market. Most of these can be brushed, sprayed etc. Very simple to use and most will do what you need. But you will need to clean the area after you use the product and spray something over the top of the area. This could be the color of the car or if it is out of sight then some flat black Rust-Oleum will do the trick to keep the areas protected from the elements.
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I am Matt K.

[63 vwnotch]

Ospho is decent and can be readily found at Ace.. tends to get in nooks and crannies some other products wont.. can be brushed, sprayed with and old windex bottle.. Over that id also recommend good ole oil based rustoleum in a sheen of your flavor..
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