Rust treatment products: an honest field report after using most of them.

POR-15 works as a rust encapsulant when applied correctly and I'll defend that statement. The key words are 'when applied correctly.' Surface preparation is everything. Clean, dry metal. The product requires a specific primer over it to bond to topcoat. People skip steps and blame the product.

Rust converter products have a role for surface rust in areas you can't fully access. They don't replace proper metal repair. They buy time.

The correct answer for structural rust is still: cut it out, weld in clean metal. No product encapsulates structural rust into structural metal. Physical replacement is the only reliable solution.