It is, of course, inconvenient you are dealing with rust on your knife. Rust, however, is not covered by warranty. Fortunately, you can prevent rust and, if you do find some rust, you can also easily remove it.
All knives can rust, even if the knife is made from 'stainless' steel. It is always the result of (a combination of) external factors: moisture, acids and salt. Think of sea air or fruit acids. The trick is to properly clean and maintain your knife. Because there are different kinds of rust it is always a good idea to give you a small overview of which there are.
- Flight rust: Rust can even occur when doing the dishes. If you do put your knives in the dishwasher, with, for instance, cutlery or a pan that has already been affected by rust, you run the risk of flight rust. It basically 'flies' through the dishwasher, and adheres to a new surface. This type of rust can be recognized by the small superficial spots.
- Pit corrosion: With pit corrosion you are basically dealing with a stain that emerged around the 'pit'. Stainless steel won't oxidize at an air humidity up to 70%. That is achieved by adding approx. 15% chromium to the steel. When the layer of chromium oxide is damaged, a new layer emerges on its own. However, minor damage to the chromium oxide layer and a drop of water can cause pit corrosion.
- Patina: Does the steel have a high percentage of carbon? If it does the blade is rock-solid, but not corrosion resistant. Think of Robert Herder, Opinel and Eden Kanso Aogami knives. This means that the knife will quickly discolour, especially when you are dealing with fruit acids. This is also called a patina, and not something you have to worry about. The patina partly ensures that the knife is not as prone to rust in the long run.
What can you do to prevent rust?
In most cases it is enough to wash and dry your knives by hand after use. Make sure that the steel is not exposed to corrosive substances (fruit acids and salt (sweat)) and store it somewhere dry. If you occasionally also treat the blade and handle to a drop of oil you know that the chances of rust are next to nothing.
How do you remove rust?
With the tips mentioned above you make sure your knife remains free from rust. Did you accidentally leave your knife in the sink, or are you dealing with flight rust? Don't worry. You can solve it!
There are numerous solutions such as soaking in vinegar, lemon juice or cola or leaving the knife in an onion or potato overnight. We don't recommend this method, however.
It is best to basically erase rust. You can do so with the Naniwa Rust Eraser or a normal eraser. The eraser will polish the metal, so look out for scratches or a dull effect.
Another effective method is a polishing cloth with a little Flitz. With it you remove the layer. Because we are convinced of the results we will send you a packet of Flitz so you can experience it yourself!
More information about warranty can be found here.