How to treat rusted metal shed roof?

[Cranswick]

Hi l have some rust on my shed roof, not sure what exact metal is , some sort of corrogated steel, its silver color, When l paint it

with Dulux Metal sheild rust primer ( Below) does it matter if l paint over some of the rust and theres still rust on the roof underneath the primer, will this primer kill or convert the rust underneath? so when l paint on top the rust underneath wont grow back. ALso is Dulux metal sheild the best primer to use if l also want to kill the rust or is there a better one

[EricL]

Hello @Cranswick 

My apologies I thought you were treating galvanized roofing. I suggest following @MitchellMc's recommendation regarding treating the rust on your metal post. The post is often made of standard steel and is galvanized coated. Using the Ranex or White Knight will be ok as the area will be cleaned off with turpentine. Once it has dried off you then cover it with Metalshield Rust Primer.   

If you need further assistance, please let me know.

Eric