How to Remove Rust From Knives: Easy Ways to Clean Rusty Knife

What Is a Knife?

A knife is a cutting tool. It consists of a blade and a handle. The blade is a flat hard steel object which has a back spine and a sharp cutting edge. The knives have an ancient history. These are in use since the pre-historic age.

The knives have a lot of types according to use. There are combat knives, ritual knives, utensil knives, kitchen knives, surgical knives, shoemaker’s knives, and many more. 

Even each of these types has a lot of variety, for example, utility knife, paring knife, steak knife, etc are different types of kitchen knives

The knives have regional and religious variations also. Such as, Kripan is a ritual knife in Sikhism. Kiyala is a ritual dagger in Buddhism. The Santoku knife which is a kitchen knife is of Japanese origin, while the chef knife is European.

Irrespective of types of knife, every knife has two essential parts. Those are handle and blade. The steel blade, which is flat and thin, is most likely to catch rust.

What Is Rust?

Rust is a brownish covering that forms on iron items. Rust forms on iron objects when they remain in moist conditions or a humid atmosphere for a considerable time. Scientifically speaking, rust is a by-product of the oxygen reacting with the iron in the presence of the water. This reaction produces oxides of the iron. The chemical formulae of these oxides are FeO, Fe2O3, Fe(OH)3, and FeO.Fe2O3.

The rust, on an iron substance, can be one of these oxides or can be a combination of different iron oxides.

Rust on Knives

How Do Knives Catch Rust?

The knives have a blade of steel. Steel is an alloy of iron. 

In daily use, this blade remains in contact with water and air. In some cases, their storage space is humid. The kitchen knives have very long exposure to wet conditions. Sometimes, chefs or cooks leave those knives in the dishwasher for a long time or do not clean the blades properly after use. 

These conditions are favorable for rusting. Hence, the iron present in the blade reacts with the air, and it starts rusting. 

How Is Rusting Harmful to Knives?

Rusting converts the outer surface of the iron objects into brownish powder. If rust remains for a long period, it splinters the surface into little brownish flakes. Ultimately, by this process, the whole iron item converts into rust.  The blades of knives are also iron objects. Besides, those are flat, thin, and have a slim cutting edge.

The rust damages the cutting edge and makes it easily breakable. Moreover, the blade loses its iron contents. Hence, it becomes weak and brittle. Therefore, we should remove the rust from the knives, as soon as it sets in.

How to Remove Rust From Knives?

There are many household techniques to remove rust from knives. Household items like baking soda, vinegar, dish cleaner, and even some vegetables are quite capable of removing rust. Let’s look at some of these methods below.

1. By Using Vinegar

vinegar to remove rust

First of all, clean the knife from dirt and wipe it dry. Pour vinegar in a bowl. Dip the knife into the vinegar. Leave it there for some time. 

After a few minutes, take the knife out of the bowl. If some rust stains are still there, soak a piece of cloth in vinegar, and rub over the stains. Now wipe the knife gently with a soft and clean piece of cloth. Your knife will be rust free.

2. By Vinegar and Dish cleaner liquid

Wipe clean the knife to make it dry and dirt free. Now take vinegar and dish cleaner liquid in equal parts in a big bowl. Stir it to mix it well. Put the knife in this solution for a few hours. 

Now remove it from the solution. If there are some stubborn stains, pour a little solution over the stains and rub with a scrub. Wipe the knife. Rust stains will go away.

3. By Sodium Bicarbonate

Take Sodium Bicarbonate or baking soda in a dish. Add a little water in it to make a soft wet mixture. Now cover the blade of the knife with this mixture. 

Keep the knife in this condition for a few hours. Now, rub the blade with a soft scrub gently to clear off the baking soda from it. Now, wipe the blade clean. This procedure will remove the rust stains.

4. By Baking Soda and Lemon


Cover the knife with dry baking soda. Cut a lemon in two halves. Take half a piece of lemon. Squeeze some lemon juice on baking soda that is over the knife.  This process will make a paste. Now take the half piece of the lemon. Rub this paste over the knife with the inner side of the lemon piece. The lemon juice has citric acid. The combination of baking soda and citric acid will remove the rust.

5. By Potato

Wipe clean the knife. Take a big piece of potato. And insert the blade into it.  Leave the blade within the potato for some hours. The potato juice will clear all of the rust stains. Discard this potato because it has absorbed rust from the knife. So, it is harmful for human consumption.

6. By Onions

Take an onion, and move the blade of the knife back and forth many times into it. The chemicals in the onion juice will dissolve the rust.

7. By Abrasive Substances

There are two household abrasive substances- steel wool and sandpaper- in our home. Rub the blade of the knife with any of those gently and carefully. It will remove the rust stains from the knife.

8. By Sand

Scrub the knife with sand or sand-rich soil. The sand acts as an abrasive. It will remove the rust.

Final Words

In the article above, we have taken a glance at some techniques to remove rust from knives. But we have to be very careful and attentive while doing so. All knives have a very sharp cutting edge.

We can sustain an injury if we are not careful. Moreover, the use of excessive force while scrubbing the knife can damage the thin cutting edge.

Now the last but not least, there is an old saying that “prevention is better than cure”. We should take proper care of knives while using them and after use. We should clean them properly, and keep in a dry place after use. So, they do not catch rust, because, rust ultimately deteriorates the knife.

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