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Water-based or Oil-based paint for the rusting of nails?

I am doing a Plan and Design Lab for science class. We are not supposed to actually do the experiment; we must only write it.
I would like to know which paint is more effective for preventing the corrosion of nails, water-based or oil-based paint. Thanks.

Nicolette R.
student - Trinidad
February 22, 2011

While I'm not 100% sure, I feel strongly that an oil based paint would be more effective. The corrosion of nails (assuming an outside environment) would likely be caused by water reacting with the metal in an acidic environment (enter acid rain). A water based paint wouldn't be much of a barrier but an oil based paint should keep the water off of the nails and prevent the corrosion.

Peter Vigeant
- Perryville, Missouri, USA
April 6, 2011

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Nicolette,

This is one of those questions I hate to see set by teachers! There is no way of saying which is better as there are literally thousands of formulations for paint, both water and oil based (e.g. epoxy based, polyurethane based, acrylic based, cellulose based etc...). The important thing that affects corrosion resistance is the additives they put in the paints. Another factor that affects it is the thickness of paint applied.

The question you have been asked needs more definition, otherwise your answer could quite easily fill a library!

Brian Terry
Aerospace - Yeovil, Somerset, UK
April 8, 2011