It’s a sad but unfortunate fact of life that metal rusts. Sometimes rust is called patina like when copper turns green after decades of exposure, but for most of us it’s just plain rust and we hate it.
Sure there are some times where choosing the right fastener has a lot to do about whether you have rust or not, but sometimes, you’re stuck with what you’ve got or you want to restore some gorgeous old hardware to its original splendor.
I’ve got some tricks up my sleeve to help you stop rust and send it running for the hills. None of these tips are complicated and they can all be done with simple items from the hardware store, so let’s get to it.
If your main focus is on restoring your old hardware, read this supplemental post as well: How To Restore Old Hardware.
Start With a Clean Surface
The first thing you’ve got to do is get a clean surface by cleaning off the existing rust. For this, I use a couple things depending on how severe the rust is.
- Light surface rust – Use 000 or 0000 steel wool and polish the surface until you’re free of rust and have a smooth surface.
- Moderate rust – Depending where you are on the rust scale, a more aggressive steel wool like a 0, 1, 2 grade may do the trick and then finish with the 0000 to put some polish on the surface.
- Heavy rust – If you’ve got heavy rust and pitting of the surface but things haven’t been structurally compromised and there are no missing pieces, then you can use a wire wheel on either a bench grinder or angle grinder to grind off the oxidized portions. A sanding flap wheel is another good attachment for the angle grinder to clean the surface. When you’re done, go back to the fine steel wool to polish everything smooth.
Once the surface is clean, you’ve got something you can work with.
Keeping Rust at Bay
Now that you’ve got a clean surface, you have to protect it to prevent rust. The minute iron or steel is exposed to the air, it begins to rust, so don’t polish the rust off and then let it sit overnight. It began rusting the minute you set the steel wool down.
Pre-treat with Ospho
The first thing I always do is give the metal a bath or at least a good coating of Ospho. Ospho is a product that is essentially phosphoric acid (I know it sounds scary, but it’s at almost every paint store and hardware shop). For the chemistry dorks like me, phosphoric acid turns iron oxide (rust) into iron phosphate. This is an important first step because it transforms all the rust it touches (even the microscopic rust you don’t see yet) into something inert which can be painted or coated safely.
Always wear gloves and eye protection when using Ospho. It is not something you want on your skin, so read the safety instructions before using it. If you want a more gentle option, try Coca-Cola. Sadly, it’s got the same phosphoric acid in it that not only fights rust, but also has the added benefit of causing cavities.
Now you’re ready to protect against rust. I avoid most water-based coatings because water and metal are not friends and should be separated like squabbling teenagers. Here are my favorite non water-based options.
Rust Stopping Coatings
1. Boiled Linseed Oil (BLO)
This is the old school rust stopper. Wipe a good coating on any tools or hardware and let it dry for about 24-48 hours. The oil forces water out of the surface and eventually dries to a thin soft coating. This can gum up intricate moving parts especially in heavy applications, so stick with non-moving metal pieces for the best results. Read how to work safely with BLO before you try this one.
2. Penetrol
Penetrol is not just for making oil-based paints flow smoothly. It is extremely versatile and works as a great coating for metals to keep them protected from the elements. Like BLO, it creates a soft protective layer and displaces water. It dries a bit faster than BLO and that always comes in handy. Just wipe a couple coats on and let it dry overnight or 24 hrs and you should be good to go.
3. Clear Coat Spray
I’ve used spray polyurethane, lacquer and a few others but one of my favs right now is called Rust Coat Enamel by Do-it-Best. The Rust Coat Enamel comes in a lot of colors but I just get the clear gloss spray can and coat everything metal that will be exposed to the weather or not. For non-historically sensitive projects, it coats great and really does seem to protect against the rust. It’s a Xylene based spray paint, so no water-based materials to cause rust.
4. Oil-Based Paint
If you’re restoring something like a cast-iron clawfoot tub or something else that will be painted instead of appearing to be bare metal, then you always want to prime and paint with an oil-based enamel paint. Enamel paints dry harder than normal paints and oil-based makes sure that no water makes contact with the metal. Always give at least one coat of primer (oil-based as well) and then 2 coats of paint for maximum protection.
Whatever coating you use to protect the metal, there is some maintenance involved, especially if there are moving parts or the items are stored outside. The weather is brutal to coatings on metal, and so keeping up with a rejuvenating coat every once in a while is always a good idea to stop rust from forming.
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I love old houses, working with my hands, and teaching others the excitment of doing it yourself! Everything is teachable if you only give it the chance.
what 2 use on aluminum rusted srew on roof
what can u use on a aluminum roof screws
You shouldn’t need anything on aluminum because it doesn’t rust.
Great post! I have 3 enamel coated washing bowls that my grandmother’s family used during the depression. Two of them I plan to use for decoration and the barely rusted third one for gardening. I’m going to use the ospho as prep, but what do you recommend as the coating for the 2 that will be decoration? I don’t want it to be glossy. Thanks!
I want to buy lawn decoration that is an old shovel that has been sculpted into a scene with a horse and barn. It is already very rusted and is thin. Can I stop the rust from continuing?
Amazing post! It is good to find an expert who can guide us on the right technique to remain hassle-free. Thanks, mate for sharing such a great post. I was able to unlock the true potential to remove corrosion from the critical area of my own farm.
I have my Grandfathers old syth and would like to hang it on the outside of my shop. Combination of wood and metal. How should I treat it.
Thanks
Hi, I have a old steel roller used to flatten lawn. It is the type you fill with water to give it weight.
It is heavily rusted on the inside to the extent that their are some pin holes that I will fibreglass over on the outside.
What inexpensive/easy product or treatment can I add to the inside to treat it and stop the rust?
thanks, Gary
Hi. I would assume you can’t get your hand in the steel roller. I would use ospho inside the roller. Pour it in and move it around to coat all the surface. You will have to drain as much of the ospho as you can. Let dry in the sun during the day, but take it in at sundown. Do this for a 3 days to dry. I would then pour in some Rust-oleum aluminum paint thinned with 15% acetone. Pour it in and move it around to coat all the surface. You will have to drain as much of the paint as you can. I would use PC-7 Epoxy to fill the outside holes. It will work butter then fiberglass. Good luck!
Scott, problem is a weather worn wrought Iron fence. Rust has set in: front yard near SPRINKLERS. WHAT CAN BE USED TO STOP THIS RUST?
Hey! Informative Post.
That was a great read. I used PURIT Multiclean to clean the rust formed in parts of my washing machine, it was worth the try & just wanted to share
I’m trying to treat rust inside the rocker panels (we call them sills in Australia).
I’ve cut some holes to get a wire brush inside but the removal will not be thorough.
I was considering spraying Ospho , letting dry for a few days then a spray of Penetrol
Is that something you’d recommend?
Thanks
Great info 🙂
I am the only female at a commercial garage. They have since moved and the washrooms for techs and mechanics is….ummm, biologically unsound? I was given the green light to redo the entire room but was asked to try and use materials on sight.
So lots of wood and lots of steel panels. I thought I would panel the walls with the steel but as it will be close to running water/humidity I am not sure it will remain in good shape. Any suggestions? Sorry if this is the wrong thread to be inquiring about this….
I just purchased new lanterns for the outside of my house. I don’t know what the metal is, but I just read a review that says they rust easily. What would you suggest I use to prevent rust.? Thank you so much!
Marilyn – as Scott stated in his “How To: Stop Rust For Good” blog, I would go with a clear spray polyurethane or lacquer spray. I’ve used it on outdoor metal sculptures and it seems to work fairly well. You may have to reapply it after a couple of seasons …
I need your advice – I’m a scrapbooker and the rings in my albums always rust here in Hawaii where it’s very humid. So I’ve been looking high and low for a solution that I can apply onto the metal rings to help prevent the rusting – Could you recommend the best option? Your blog post has been the most informative that I’ve found so far – but the products you mention sound a bit scary. BLO will definitely mildew in my area so wondering if Penetrol or the clear spray would work better?
Take a look at BoeShield. Easy to apply and won’t gun them up.
I’m re doing a Large Parrot cage so once I’ve cleaned sanded what can I use tp inhibit rust that is non toxic I will be finishing with a water based all natural Non-voc paint..(parrots bite on the bars and have Very powerful bites so it has to be safe.)??? These cages cost a fortune so I appreciate the help {5ft tall)
Thanks!
I have treated wood stairs at a beach house. Some of the nails used were not galvanized so they rust through the paint frequently despite using Rustoleum rust prevention. The nails are basically countersunk into the wood. You suggest Ospho and clear coat spray. Which woul dbe better for this application? After using one or the other rust inhibitors, I would use an epoxy to repair the holes then paint. Will that work? Thanks!
ospho then use a rust inhibiting spray once the ospho has dried
I had some 5/8″ chain that looked like it came off the titanic. I soaked them in a pail of regular white vinegar from Walmart for 3 days then pressure washed at the car wash.
It got them completely rust free. I tried spraying with silicone spray but have seen a few spots of surface rust. I’d like to paint them but I think it would chip. I use the chains inside as part of a fitness routine so oil and mess is not a good thing. A little rust dosnt bother me but I don’t want them to be covered in a thick layer.
I’ve heard that heating things like sash locks before coating with Penetrol helps to “season” them, similar to treating a cast iron skillet with cooking oil. Any thoughts?
I have heard that too Larry and though I haven’t tried it I think it bears a little testing in the shop soon. Great point!
You should take part in a tournament for one of the best websites on the internet.
I’ll recommend this website!
Ha ha! Thanks James!
What coating would you recommend for something that has moving parts, like a sash lock for example? Evapo-rust is pretty amazing for removing rust from items. I recently used it to restore a vintage hand trap thrower and it worked great & didn’t damage the mechanism.
Any of the coatings mentioned work well on sash locks. I usually use the clear coat spray I listed unless the client wants a satin finish in which case penetrol is the way to go.
Good to find an expert who knows what he’s taiklng about!
Great post! I learned a lot from this one. I’ll be saving a digital copy on my thumb drive.