Cor Ten Steel not rusting

[tomtucson]

I have a large facade of expanded steel plate and structural members that is oily and grimy and is not rusting. Is there a process to initiate the oxidation, does it need blasting? Any info appreciated.

 

[Scott Stone]

They are looking for the rusty look?
If you clean it really well with NaOH, it will remove the oil. If they want to accelerate the rust, give it a good acid bath, but don't rinse it. If you include a non-ionic surfactant, the acid will lay down better, and spread more evenly.

 

[Ron Musgraves]

Won't acid continue to eat?


Text me anytime for question 480-522-5227

 

[Scott Stone]

Not forever. It can only eat until it is neutralized, either chemically, or by the oxidation of the metal. That is why a drop of hydroflouric acid will burn you, but a tablespoon will kill you.