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i have a ’00 Lanos it has some minor surface rust on the door sill (only can be seen with door open) it also has rust on the steel rims. I bought some spray paint and primer for another project and thought that since i had the can of primer (Rustolium) that once im done with the project i got it for i would use it to repaint rust spots on my car. the can states use sand paper or a wire brush. I have no power tools other than a drill. What grit of sand paper should i use? I am simply going to paint over the rust as it is all surface rust the colour of the car is code A3U Polly Silver Metalic. how would some simple indoor/outdoor silver paint match the car? Do i need special RIM paint or can a can of black indoor/outdoor paint do this job too? I also have some nicks and scuffs in the bumpers to touch up. Does AutoZone have touch-up paint?
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Hi Matthew. I would use 180 grit sandpaper to remove all of the rust. Once it’s all gone, clean the surface thoroughly with some solvent. Then spray primer on the area. Once that dries, sand it all smooth with 320 grit. Then it is ready to be painted. Since you are not going to blend and clearcoat the vehicle, just grab any silver spray paint that matches your paint. It will still be noticeable color difference but, it looks like your main concern is to stop the rust from getting worse. Call your local autozone and tell them the paint code. They should sell small spray cans. Hope this helps. PS… I own a body shop.
i thought the entire point of Rustolium paints and primers was that it was designed to adhere to existing rust?
I never used rustoleum before to repair rust damage on a vehicle and am not sure exactly how it works. I do know that The more rust you remove before painting, the longer your repair will last. After sanding, you can also prep the area with a vinegar/water solution to help kill any surface rust. Rust will ALWAYS come back. The more prep work you do, the longer it will take before it returns.
I hear that all the time – rust will always come back. Well, why? If it is painted and all sealed by the paint why should that spot be any different than any other surface of the vehicle?
I am not a scientist and do not fully understand the nature of rust growth… But I am a highly skilled body shop owner. I was only trying to give you tips based on my many years of expertise in this area on how to repair your rusted vehicle. Go ahead and grab a can of rustoleum and spray over the rust. It’s your car and your money. Good luck… Hope it works well for you.
[quote=”Aaron A.” post=107550]I am not a scientist and do not fully understand the nature of rust growth… But I am a highly skilled body shop owner. I was only trying to give you tips based on my many years of expertise in this area on how to repair your rusted vehicle. Go ahead and grab a can of rustoleum and spray over the rust. It’s your car and your money. Good luck… Hope it works well for you.[/quote]
I’m not the car owner, I’m not a body repair person, I didn’t figure you were a scientist but I figure if you are a body shop owner you do have expertise. So, I’d be interested in anything you can tell me on this subject, what you have seen, what are your experiences? I do do a little touch up painting in my shop occasionally and I’d like it to be successful.
Sorry about being short with you… I didn’t look at the post good enough and thought you were the same person that started it… Looking back, your question makes more sense. I found this info and actually learned a lot from it myself. That was a great question you asked and I have just been too lazy in the past to do any research. Thanks, Aaron
What Rust Is
In order to understand how rust works and spreads, you first have to understand what rust is. “Rust” is the common name for what is scientifically known as iron oxide, a form of corrosion that occurs when iron (or one of its alloys, such as steel) reacts with oxygen and there is water (or heavy air moisture) present.
Other metals have oxidation processes as well, but they do so differently and the result is not commonly considered rust. Copper corrosion is green (and accounts for the color of the Statue of Liberty) while aluminum corrosion spreads extremely slowly.
The Molecular Process of Spreading
The process of metal corrosion is an electrochemical process. It happens on a molecular level as electrons transfer from iron molecules to the surrounding oxygen molecules, changing the makeup of the iron and turning it into rust. This is happening to iron all the time. In fact, it is impossible to find a piece of iron without at least some oxide present within it. However, the rate of rusting is usually slight and slow but is accelerated by water, especially if the water has a high concentration of electrolytes (substances in the water that help electrons move).This is why the presence of salt causes rust to spread more quickly.
Spreading
Rust does not spread through contact like a biological infection. Instead, the process of iron oxidization occurs independently based on the conditions surrounding a particular piece of metal. This means that if one part of the piece is exposed to water, oxygen, and electrolytes but the rest of the piece is kept clean and dry, the protected metal will not rest at the rate of the wet metal.
Iron alloys will have different corrosion rates based on their makeup.
How Prevention Works
Steel is commonly protected from rusting through a process known as galvanization. In this process, the steel will be dipped with a coating of zinc, which protects the steel by reacting with water molecules. If the zinc coating on a piece of galvanized steel is scratched or scraped away, the exposed area will be vulnerable to rusting.
Read more : http://www.ehow.com/how-does_4613667_rust-spread.html
Tell me where I am wrong here:
If you see some fuzzy rust and clean it up and spray with primer and topcoat I say without further paint damage you have a permanent fix. If it is pitted then maybe not a permanent fix. Panels are thin and the pit may actually be a connection to the backside of the panel.
However, that’s not usually how rust occurs. Instead you see paint blistering and when you knock that off you find rust that has come from the backside of the panel. Fixing the outside is fixing nothing.
So, lets say you cut the rusted area out and weld in new metal. When you grind down the weld it is going to have to be a perfect weld or you will have a pinhole connection to the backside of the panel under the paint. So, I can also see that rust coming back.
was not able to find 320 grit i got a combo pack of 150 180 and 220 grit. IDC much if it comes back i just dont like looking at it when i open my door. Also i noticed at the same spont on the bottom of the door its rotted out there too the door is rusted though (does not show on the outside) but is WAY worse than the surface rust on the door sill. Any tips on how to sand and spray that lip on the bottom of the door?
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