Just Sand It?
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Corblimeyguv
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No such thing as 'non-rust oxidisation'.
Oxidisation is the posher word for rust. Corrosion is another.
It may be a barrier coat to stop the paint reacting when it was painted, or the remnants of the primer.
No such thing as 'non-rust oxidisation'.
Oxidisation is the posher word for rust. Corrosion is another.
It may be a barrier coat to stop the paint reacting when it was painted, or the remnants of the primer.
Re: Re:
I’m not sure that’s correct, further research I found the following
Either way I got going the sandpaper anyway because there was red rust to deal with too
Stainless won't darken like non-stainless does, in that it doesn't oxidize the same way by exposure to the air (oxygen). When 'carbon' (non-stainless) steel oxidizes, the iron reacts with oxygen to form iron oxide (Fe[sub]3[/sub]O[sub]4[/sub]), which is dark in color (almost black). With stainless, the added chromium in it will immediately oxidize instead, and it's essentially colorless or clear, with a very, very thin layer of chromium oxide on top of the steel. The chromium oxide layer essentially shields or prevents the underlying iron in stainless from oxidizing, which is what gives the steel it's 'stainless' properties. If the steel is scratched or abraded to remove the chrome oxide layer, the underlying chromium in the steel will again oxidize immediately, restoring the 'stainless' protection to the surface.
BTW, when 'red' rust forms on steel, it's due to the iron reacting to oxygen in the presence of water. The oxide formed by 'rusting' in such a manner is chemically different, with the formula Fe[sub]2[/sub]O[sub]3[/sub]. The added chromium in stainless steel will also protect against that type of oxide forming on the steel, by the same means.
Corblimeyguv":1caevj7d said:
I’m not sure that’s correct, further research I found the following
Either way I got going the sandpaper anyway because there was red rust to deal with too
Stainless won't darken like non-stainless does, in that it doesn't oxidize the same way by exposure to the air (oxygen). When 'carbon' (non-stainless) steel oxidizes, the iron reacts with oxygen to form iron oxide (Fe[sub]3[/sub]O[sub]4[/sub]), which is dark in color (almost black). With stainless, the added chromium in it will immediately oxidize instead, and it's essentially colorless or clear, with a very, very thin layer of chromium oxide on top of the steel. The chromium oxide layer essentially shields or prevents the underlying iron in stainless from oxidizing, which is what gives the steel it's 'stainless' properties. If the steel is scratched or abraded to remove the chrome oxide layer, the underlying chromium in the steel will again oxidize immediately, restoring the 'stainless' protection to the surface.
BTW, when 'red' rust forms on steel, it's due to the iron reacting to oxygen in the presence of water. The oxide formed by 'rusting' in such a manner is chemically different, with the formula Fe[sub]2[/sub]O[sub]3[/sub]. The added chromium in stainless steel will also protect against that type of oxide forming on the steel, by the same means.
Corblimeyguv
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I'm no metalist or expert on oxidisation, whether it be bi-metallic or not.
I was just giving a suggestion, no more than that.
I'll leave you to investigate it at a molecular level and get back to watching youtube
I'm no metalist or expert on oxidisation, whether it be bi-metallic or not.
I was just giving a suggestion, no more than that.
I'll leave you to investigate it at a molecular level and get back to watching youtube
all good, same here while I wait for a rust converter to do its work
I like threads like this because I might learn something. Anyhow, to answer your question, at a guess, and of course
having a do with Saturday wine......what makes you think the frame was sand blasted to shiny steel then immediately in
the seconds after sprayed? My guess is that it was left for a hand full of days or weeks before being sprayed and hence,
oxidisation / darkening happened which any primer should have taken care of to do it's job as a bonding agent.
I'm an engineer, not a molecular level mentalists.
having a do with Saturday wine......what makes you think the frame was sand blasted to shiny steel then immediately in
the seconds after sprayed? My guess is that it was left for a hand full of days or weeks before being sprayed and hence,
oxidisation / darkening happened which any primer should have taken care of to do it's job as a bonding agent.
I'm an engineer, not a molecular level mentalists.
Fook it's amazing what supply chain thinking and wine can reveal.
Duxuk
Retro Guru
I have a degree in chemistry! Sadly I've forgotten almost everything in the subsequent 35 years. I do, however, remember that iron oxide can exist as ferrous oxide or ferric oxide. Iron can have oxidation states of +2 or +3. Ferrous oxide is FeO and is blackish. Ferric oxide is FeO2 and is the red of rust. You can also get oxides with iron in both oxidation states such as Fe5O7! Glad I've forgotten most of it, really.
Giving it a good sand and primer on before any new rust forms has got to be your best bet.
Giving it a good sand and primer on before any new rust forms has got to be your best bet.
