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4th grade project: what paint is best

I'm a fourth grader doing a science project on "What brand of paint protects metal the best against rust?

Renia S.
student - Charlotte, North Carolina
2004

What are our choices? Any oil based paint that is properly applied over a properly prepared surface will beat any water based product. There are lacquers that do very nicely. How about two component epoxie or fiberglass resins. Powder coat is great. Basically, a bad question until you apply some more parameters. I doubt that any 4th grade project has the time or the equipment to determine the difference between two brands of paint, let alone 5 or 10.

James Watts
- Navarre, Florida
2004

I think I'm going with oil-based paint, water-based paint, rust-oleum, what would be the best brand of paint.

Isaiah
- Charlotte, North Carolina
2004

Rust olem is a brand name, so that is your only choice of "brands". Please note that because it is a brand and not a specific type, you have to identify that type before you can compare it to other types of that brand.

Now, how do you plan to compare the different types? How do you plan to insure that you have the identical thickness on each test part. Note that weight is not a truly valid measurement as it would run on the assumption of a perfectly identical application which is highly improbable.

James Watts
- Navarre, Florida
2004

In general the paint is not what gives you protection from rusting. Ideally before steel is painted a treatment is put on first. The simplest and best is zinc phosphate, but others are available.

Paints in general are made from three main ingredients resin also known as binder, pigments, and solvents. If you really want to spend the money the best resin system would be a fluorocarbon. For pigments rust prevention is generally done by adding strontium chromate. Most paints you will find in a local paint store are alkyd based resin systems with zinc based pigments for rust prevention.

Incidentally the last solvent is in the paint to make it liquid enough to apply then it evaporates. Good luck with your project.

Ronald Zeeman
- Brampton, ON, Canada
2004

Hi Renia,

I hate to give a cop-out answer, but you'll probably find that the most expensive paint will give you the best results, you get what you pay for and if you buy cheap, you get cheap(I'm talking $2 to $5 dollar cans of spray paint here). What you need to test should be the primers, each brand of paint makes their own primers so you should not have a problem finding 2 or 3 different kinds, make sure the can says that it's usable with metal. I'm agreeing with Mr. Zeeman in that the top coat is basically for cosmetic purposes. I'm interested in knowing what kind of testing you will be doing to get your results.

Good luck!

Sheldon Taylor
supply chain electronics
Wake Forest, North Carolina
2005