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Switch Exterior Fasteners to Something That Won't Rust?

Does it make sense?
Galvanized Steel
Stainless Steel
Carbon Steel
Zinc Plated
Others

So that way they don’t rust?

What fasteners are you talking about . Some one here might think you are Trolling with all these weird questions.

It’s a serious question. Just generally speaking. Anything exposed to the elements. I’ve notice on some fasteners they get all rusty, turning the metal or plastic surface they rust on all rusty. I don’t like it. Seeing surface rust from a faster on the surrounding area. So I’m wondering if replacing it with something that won’t is a good idea.

Galvanizing is the process of applying a zinc coating.

Carbon steel is just that. No coating.

Stainless doesn’t rust. But it’s expensive.

Chromed plated steel doesn’t rust. But again, it’s expensive.

That’s why hardware is galvanized.

Cheap!

Tester

So I should do it?

Do what ? You can do anything you want , it is your money .

I always use stainless steel license plate screws, for what that’s worth.

Is there any fasteners I shouldn’t do this with?

Unless you have mechanical engineering background, stay away from any structural fasteners. Those are chosen with specific performance characteristics and you can easily do more harm than good by installing hardware that is not designed for the application.

Case in point- guy at work almost killed himself and others when his plow fell to the pavement at 70mph on the expressway. He had decided he didn’t like the oxide forming on the lift chain hardware. Swapping it out, he chose a nice shiny but very hard, high grade bolt. Exact opposite what you want there. It snapped under repeated stress and down came the plow. Lots of bent metal but no one seriously injured fortunately. If you don’t understand it, don’t substitute any structural hardware elements.

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Stainless steel fasteners may experience some galling problems.

https://www.essentracomponents.com/en-gb/news/product-resources/how-to-prevent-galling-on-stainless-steel-bolts

The ARP-bolt website also has some good info on the + and -'s of various fastener materials.

Just to add my 2 cents, if you are talking about trim, they have pretty much eliminated that and just glue it on or use those button plastic fasteners. Way back there were holes in the sheet metal with metal retainers for the trim. Always rusted the sheet metal. Much better now.

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Sure, use stainless steel screws

It would help greatly to tell us what in the world you are trying to repair or re-fasten here. Stainless is just that…its stainless…it doesn’t rust (usually depends on quality of the metal honestly)

But what project do you have in mind here? What fasteners are you looking to replace? For what?

As far as galling, use anti-seize.

And also remember that different metals in contact each other can cause faster corrosion in one of the metals. So unless you know what specific metal the fastener is being fastened into, you should probably stick with whatever is stock.

I see no one mentioned corrosion caused by electrolytic action - that is the difference in electrolytic potential.

The best example is aluminum and steel, where the aluminum corrodes (which normally doesn’t), but the steel doesn’t (which normally does.) You can see this on alloy wheels with steel balance weight clips.

The galvanic corrosion is definitely something to be concerned about. Different metals and alloys of metal react differently. There are dozens of alloys of stainless steel alone although probably only a limited few in the fasteners of interest. Also, as mentioned, different metal respond differently to stress. A strong but brittle material could cause more harm than good.

My gut tells me that galvanized is probably your safest bet and cheapest. Also, those plastic push pins would be a no-brainer if they are strong enough for your application.

Do not use copper on steel or aluminum under any circumstances! I always knew these materials were incompatible but figured how bad can it be? I have electric fencing at my farm and the cheapest type of wire is galvanized steel. I also used some aluminum which cost more and didn’t corrode but was not nearly as forgiving to being hit by an animal or falling tree limb. I had several different heights of posts and decided to add an extra line of wire above the others to keep the goats from jumping over the top. Some of the posts were a little too short. These were plastic so I wrapped some scraps of copper ground wire around the tops and bent it into a bracket to hold wire above the tops of these shorter posts. Boy was that a mistake! The steel and aluminum wire just basically started to crumble and break within weeks! This isn’t something that takes years to happen as I expected. It happens very quickly. I was planning to replace the wire in a year or but this sped up the process.

The usual rusty place nowadays is the bolts and nuts that hold the license plate. Plastic or nylon bolts and nuts prevent that.

Don’t get it twisted… Its not as if vehicle manufacturers don’t know which fasteners will not rust… they do, in fact they are well aware. The issue is cost not a lack of ideas.

So again… what fasteners are you having a corrosion problem with and on what vehicle? Can you change the fastener type? Sure, go ahead… You are basically limited only by the depth of your wallet.

We were discussing the possibility of you changing your fasteners to some other material not what causes corrosion? Yes? Yes of course we were…

Change them to whatever you like. Titanium fasteners will look brand new when your entire vehicle is literally a pile of Iron Oxide…but one might ask…why?

Actually, aluminum is very easily corroded. What most people normally think of as bare aluminum is clear anodized aluminum. It’s oxidized at the factory to prevent uncontrolled corrosion that eventually becomes an ugly white smut.