How to Remove Rust from Tools and Metallic Components
Are you looking for ways to restore your old rusty tools? Or maybe you found a stock of bolts and screws in your workshop, but they have all turned rusty brown – is there any way to make them usable again?
Yes, there is! And this is what today’s post is all about. There are multiple solutions to the rusting problem with tools as well as all metallic parts in general, especially those parts and components that are made from ferrous metals.
The problem of rust is not confined to our toolboxes only, it is an industrial problem as well. Many forms of surface treatment are available to prevent rusting of mechanical parts, however, environment can find a way to compromise the preventive measures and force us to think about corrective measures.
In this post we will discuss the following main techniques and methods,
1. How to remove rust from tools using home remedies (including vinegar, baking soda, Coke, potato & soap, lemon juice and even ketchup).
2. How to remove rust from tools using chemicals (including citric acid, hydrogen peroxide, WD 40 and solvents such as Evapo-rust).
3. How to remove rust from tools mechanically without using chemicals (including the use of power tools such as angle grinder, rotary tool, palm or orbital sander and hand tools such as wire scratch brush, steel wool and abrasive cord).
4. How to remove rust from tools using industrial processes (including sand blasting, wet blasting, electrolysis, vibratory finishing and ultrasonic cleaning).
So, without further due, let’s begin.
There are multiple ways of restoring rusty tools using substances that you can easily find at your home, especially your kitchen. We have discussed the ones that we found most effective.
If the tool or part you are trying to clean has some rusty spots, you can soak a towel in white vinegar or apple cider vinegar and then clean the rusted area with that towel.
However, if your tool is full of rust, it is better to leave the tool dipped inside a bowl of vinegar overnight. After 10-12 hours, remove the tool and clean it using water. Check the time lapse video below to see how it works.
(Video Credit: Alley Picked YouTube Channel)
The Science behind the magic: If you are wondering how it happened, you need to recall your chemistry class on acid and base. Rust is formed when metal reacts with oxygen present in the air and forms metal oxide.
Metallic oxides are bases in nature (there are some exceptions though for example magnesium is a metal that forms a basic oxide). On the other hand, vinegar is acidic because it contains 5-7% acetic acid. If you remember what happens when a base reacts with acid, you’ve unveiled the mystery. Acidic vinegar reacts with basic rust (metal oxide) to form salt and water leaving the tool behind clean.
Using baking soda for removing rust from your tools is a simple two step process. Step one is to mix a little water with a lot of baking soda to make a thick paste and apply that thick paste over the rusted area of the tool.
Step two is to scrub the tool gently with a scrubber or a tooth brush and you will see the rust coming off. You might have to repeat the process for satisfactory results. Check out the short video tutorial below for seeing how its done.
(Video Credit: essortment YouTube Channel)
Limitation: This method is not very convenient when the whole tool has become rusty. It is more useful when you only have to remove a patch of rust.
Chemistry behind the scenes: If you are familiar with the fact that both baking soda as well as iron oxide are basic in nature, the most interesting question becomes how does it work? Acid and base reaction is understandable, however, base reacting with a base?
As per our research, the reason why it works is not because of a chemical reaction but the reason is more mechanical in nature. Baking soda is comparatively abrasive in nature and when its paste is applied over a rusted surface and scrubbed, it takes the rust off through abrasive reaction rather than a chemical reaction. The granules of baking soda enhance the scrubbing ability of scrubber and remove the layer of rust from metal surface.
You can also use lemon juice to remove rust from your tools. You can squeeze lemon juice over the rusted area; allow it to set for a few minutes and then scrub it off. Adding salt in the process has been noted to improve the rust removal. Check out the video tutorial below to see it in action.
(Video Credit: Crisium YouTube Channel)
Chemistry behind the process: Lemon juice has citric acid as one of the main constituents that reacts with rust in a conventional acid base reaction to dissolve it.
In United States, 93% of the beverages have a pH of less than 4.0 (acidic) as per a study conducted by American Dental association in 2016. Phosphoric acid is the primary reason behind their acidic nature and as discussed earlier, acids react with basic ferrous oxides (rust) to neutralize them thereby removing rust from the surface of your tools.
The method is simple. Just leave your rusted tool soaked in Coke or Pepsi for 24 hours and then gently scrub it with a wire brush or scrubber to clean off the softened rust as demonstrated in the video below.
(Video Credit: Dale Lucid YouTube Channel)
An interesting point: A lot of people quote this effect of Cola on rust and make an argument against Coke stating “If it dissolves rust, imagine what it would do to your body” however, this argument is not correct.
We’re going off-topic so let’s make it short. Lemon juice and vinegar also dissolve and remove rust so they must be equally dangerous? Instead, lemon juice is praised to be full of Vitamin C while vinegar is also full of health benefits. We are not advocating the healthiness of Cola, however, the point to understand is that our stomach is not rusty so Coke will not dissolve it.
We found it to be the least effective methods, however, it does work. To make it work, cut a potato and put dish washing soap over the freshly cut area. Now rub it all over the rusted area again and again. Rinse with water along with scrubbing and it will remove rust. However, we found this method to work only for very light rusted tools and parts.
(Video Credit: Easy Outdoors YouTube Channel)
What’s the science behind this wonderful potato hack? Potato contains oxalic acid that reacts with the metallic oxide and neutralizes it by the way of acid-base reaction thereby removing rust.
It is just amazing that ketchup can also be used to remove rust. Simply apply a lot of ketchup over the rusted area of the tool and leave it there from a few hours to 24 hours depending on how tough you feel the rust is. Then rinse with water and rust will be removed.
(Video Credit: Make Stuff YouTube Channel)
Limitation: This method is effective only for light rust and small rusty spots, not when your pipe wrench is completely rusted.
There are many chemicals that you can easily find in the market that will help remove rust from your tools quickly.
You can easily find citric acid in granular form in your nearest market as well as online on Amazon. For removing rust off your tool, simply make a concentrated solution of citric acid and soak your rusted tool in it for 2-4 hours. It will soften the rust that can easily be removed with a scrubber.
(Video Credit: Toolworks – restoration show YouTube Channel)
The science is again the same. Citric acid reacts with ferrous oxide in a conventional acid base neutralization reaction to dissolve the rust on your tool.
WD 40 is commonly used as a penetrant to free seized parts but it can also be used for removing rust. Simply spray WD 40 over the rusted area of the tool and leave it for 10-20 minutes. Gently scrub the rusted surface with a simple scrubber such as scotch-brite then clean the surface with a cloth or paper towel.
(Video Credit: ShorePoint Creations YouTube Channel)
Many companies have identified the need of rust treatment chemicals and have developed special solvents and sprays for professional as well as non-professional users.
For example, the WD 40 company sells a special “Rust Remover Soak” product that is different from the normal WD 40 spray you use in everyday applications. It is especially made for removing rust from tools, metal parts and components. It is reusable until it changes its color.
(Video Credit: Evapo-Rust YouTube Channel)
Another popular solvent in this regard is the Evapo-Rust that is also a liquid in which you simply soak your rusted tools and leave for a few hours until all rust is dissolved. It is also reusable until it changes its color.
There are many more similar products out there that can easily be found by searching for “rust removers” on Amazon or ebay. One notable advantage of these solvents is that they remove rust without the need for scrubbing in most instances i.e. when you remove the soaked tool from the solvent, you won’t have to scrub the tool to get rid of the rust. You would just have to clean it with a towel. That is so because these solvents don’t just soften the rust, they dissolve it.
Hydrogen peroxide is a very reactive chemical that can rust metals easily. It is almost ironic that the same chemical that is famous for instantly rusting iron can be used to remove rust. Hydrogen peroxide gallons are easily available in market as well as on Amazon.
To do that, simply spray hydrogen peroxide over the rusted metal and leave for a few minutes. Now scrub the metal surface while washing with water to make sure no peroxide is left on metal surface otherwise it can rust the metal as well.
Angle grinders are commonly used for cutting and grinding applications, however, special discs are available for paint and rust stripping applications. Just go to Amazon and search for ‘rust stripping wheel’ to find a wide variety of such discs.
Once you have the tool with the right disc, you just need a bench vise to hold the tool you are trying to restore and rest depends on your mastery over using angle grinder.
Limitation: This method is not suitable for removing rust from small tools such as screw drivers because it is an aggressive process and might deform the screw driving tip of your tool. It is suitable only for comparatively heavier tools such as pipe wrench handles. Moreover, this method will not remove rust from nooks and crannies of your tools.
A Dremel tool has accessories that are designed for rust removal. They have special accessories that are designed to remove rust and paint from metallic surfaces for example just look for Dremel accessory no. 428, 442 and 443 that are basically carbon steel brush accessories for rust removal, cleaning and polishing metallic objects that will fit serve the purpose of removing rust from your tool.
Moreover, due to its small size, a Dremel tool will be able to remove rust from grooves and nooks and crannies of your tools. Check out how a rusted Vernier caliper is restored using a Dremel tool.
(Video Credit: Dirt and Rust YouTube Channel)
Limitation: It is not convenient to use rotary tools for removing rust from big tools such as large wrenches and hand saws because the tool itself and the accessory is too small for such jobs.
A power sander can also take care of rust removal from tools that have flat surfaces such as hand saws and shovel. Simply use a sanding disc with 40-60 grit ratings and without applying much pressure, remove rust from your tool. Check the tutorial video below for better understanding.
(Video Credit: ehowathomechannel YouTube Channel)
If you are interested in removing rust from your tools the old school way, you need a few hand tools and a bottle of water to keep you hydrated. You can use the good old sandpaper to remove very light rust by simply sanding the rusted area. If it doesn’t work, you can notch it up by using steel wool and wire scratch brush to gently scratch the surface of the tool to scrape off the rust flakes. For getting inside tight spots, you can use an abrasive cord. All these hand tools are easily available online as well as on hardware stores.
Limitation: These hand tools are likely to leave marks and scratches on your tool. Moreover, they won’t be able to restore a tool that is heavily rusted because it would require far greater effort than humanly possible.
So far we have explained how to remove rust from your tools using power tools, hand tools, chemicals and household substances. Now we will list some methods that are more technologically advanced and either require special apparatus or technical experience for removal of rust.
You might not be able to use these methods yourself, however, you can find a facility in your town; a workshop equipped with the tools required for these methods or an expert who will charge you for getting the job done. So, without further due, let’s begin.
If you could see the magic of sand blasting, you would feel like using power tools and hand tools for removing rust from tools and hardware is a waste of time. In layman terms, sand blasting is simply directing a jet of sand on metal surface through a nozzle. Sand particles hit the metal surface and blast off the rust leaving behind smooth metal surface. We will explain the complete physics of sand blasting some other day, however, you can check the video tutorial below to see sand blasting in action.
(Video Credit: my mechanics insights YouTube Channel)
Caution: Although sand blasting equipment can be found locally as well as on online market places, however, we would not recommend you perform sand blasting yourself because it must be performed by trained personnel wearing proper protective equipment during the procedure.
Wet blasting refers to directing a pressurized stream of water through a nozzle over an object. When water strikes the tool or piece of hardware at high pressure and velocity, it just blasts off the rust from over its surface. The main difference between wet blasting and sand blasting is the media i.e. water vs. sand that is used to produce an abrasive effect for removing rust. Check the video tutorial below for better understanding.
(Video Credit: Vapor Honing Technologies YouTube Channel)
Electrolysis is another great process to remove rust from your tools and hardware. The procedure involves setting up the apparatus by using your rusted tool as cathode (connected to negative terminal of battery) and iron rebar as anode (connected to positive terminal of the battery). Solution of washing soda in water will serve as a good electrolyte.
It takes a few hours for electrolysis to work, however, once done successfully, rust comes off the tool without the need for scrubbing. You can check the video tutorial below for better understanding of how the procedure works.
(Video Credit: WOOD magazine YouTube Channel)
Electrolysis is widely used for restoration of artifacts because other mechanical or chemical procedures can compromise the small features and details of the object being treated. If you are interested in learning more about the use of electrolysis for removal of rust, we’d recommend visiting Andrew Westcott’s detailed post on the subject at qsl.net.
A vibratory tumbler is a piece of equipment that uses abrasive media and vibrations to polish objects. It is simply a vibrating drum filled with an abrasive powder such an aluminum oxide. You have to throw the tool or hardware that requires de-rusting inside the tumbler and just run it.
It will take anywhere from half an hour to a few hours depending on the condition of rusted parts to remove rust. No scrubbing is required in the process. Check out the video tutorial below for better understanding.
(Video Credit: JP YouTube Channel)
How it works?
The abrasive powder grinds against the object placed inside the drum due to vibrations and removes the layer of rust from over the metal surface just like you would do with a wire brush or sandpaper. It is just that machine is doing all the work.
An ultrasonic cleaning apparatus simply consists of a tank filled with a solvent inside of which ultrasonic waves produce agitation not visible to the naked eye. The agitation causes “cavitation” that has the ability to break the bond between rust and metal surface of your tool thereby revealing smooth surface and getting rid of the rust. Check the video tutorial below for demonstration and then we’ll talk about the science behind the magic.
(Video Credit: The Good of the Land YouTube Channel)
Science behind ultrasonic cleaning
Sound waves are simply vibrations traveling through a medium and reaching your ear drums from where they get converted into electrical signals and our brain interprets them as sound. The important fact here is that sound waves are vibrations.
Ultrasonic cleaning uses ultrasonic sound waves in the range of 20-40 kHz i.e. waves vibrating at 20,000 to 40,000 cycles per second. We cannot hear these sound waves because they are beyond the capacity of our ears, however, they vibrate the medium through which they pass.
Ultrasonic cleaning apparatus simply directs these ultrasonic waves towards a solvent stored in the tank. Vibrations cause agitation in the form of pressure variations inside the fluid and cause cavitation. Cavitation refers to boiling of a liquid at room temperature due to drop in pressure.
Cavitation is a phenomenon quite common in high speed centrifugal pumps as well as impellers where a very high speed of rotation of pump and impeller blades cause localized pressure drops in the fluid causing the fluid to boil in a bursting manner over the surface of the blade causing wear, tear and damage.
The same phenomena of cavitation is used in a controlled way to take advantage of localized boiling bursting effect to separate the layer of rust from metal surface. Ultrasonic cleaning is not only effective for removal of rust from tools and hardware but also for removal of all sorts of other impurities. Check the video demonstration below if you are interested in further understanding ultrasonic cleaning.
(Video Credit: Cutting Tool Engineering YouTube Channel)
Conclusively, choice of the right technique and method for removal of rust from tools and hardware depends on a number of factors including the type of tools and hardware being treated; level of urgency for removing rust; level of precision and finishing required; number of tools or hardware items to be treated at once and tools and equipment accessible to you. All these factors will decide which technique is best for you.
You might have to use multiple techniques in succession and combination to remove rust from the tool like the video tutorial on restoration of a very old rusted wrench below.
(Video Credit: Garage Restoration YouTube Channel)
That was it from our side. If you tried any of the methods we described to remove rust from your tools, please give your feedback. If you feel like we have left out a rust removal technique, please let us know in the comments.