Why Does a Pencil Sharpener Blade Rust after Unscrewing and Reassembling?
A pencil sharpener blade never rusts naturally, but once you unscrew the blade and screw it back again, it tends to rust easily in a few days. Another common issue is that keeping the blade open for extended periods leads to rusting as well. This phenomenon can be puzzling, but the rusting of a pencil sharpener blade can be attributed to a few factors related to exposure to moisture and air. Here's a detailed breakdown of why the blade may rust under the described conditions and how you can prevent it.
The Role of Moisture and Air
The rusting of a pencil sharpener blade can be attributed to a few factors related to exposure to moisture and air. When you unscrew the blade, you may inadvertently expose it to moisture and oxygen that were previously sealed off. Even tiny amounts of moisture can accelerate rusting, especially if the blade is made of a type of steel that is prone to oxidation. Additionally, the act of unscrewing may create micro-scratches or damage the protective coating if any, making it more susceptible to rust.
Keeping the blade open means it is directly exposed to air and humidity, which are critical components for rust formation. Rusting occurs when iron in the blade reacts with oxygen in the presence of water or moisture. If the blade is left exposed, it can easily absorb moisture from the air, leading to oxidation and rust. In a humid environment, the likelihood of premature rusting increases significantly, as moisture is more readily available, hastening the rust formation process.
Protective Coating
Many blades come with some form of protective coating that prevents rust. When you unscrew the blade, this coating can be compromised, allowing moisture and air to come into direct contact with the metal, leading to the formation of rust. Even if the blade is not exposed for long periods, it can still rust over time due to the compromised coating.
Environmental Conditions
The environment plays a crucial role in the rusting process. If the environment is particularly humid or the blade is stored in a damp area, the likelihood of rusting increases. High humidity accelerates the rusting process by providing more moisture to the metal surface, which can react with oxygen, leading to the formation of iron oxide—a common form of rust.
Tips to Prevent Rusting
To prevent rusting, follow these tips:
Keep the Blade Dry
After using or cleaning the sharpener, ensure the blade is thoroughly dried. Moisture is the main culprit in the formation of rust, so removing any remaining water will significantly reduce the risk of rusting.
Store in a Dry Place
Avoid storing the sharpener in humid areas. High humidity levels can lead to rapid rusting. Choose a dry, well-ventilated place to store your pencil sharpener.
Use a Protective Coating
Apply a thin layer of oil or use a rust-resistant sharpener. Lubricants and rust inhibitors can help protect the blade from corrosion. Regularly oiling the blade can provide an additional layer of protection against moisture and air exposure.
Conclusion
The rusting of a pencil sharpener blade after unscrewing and reassembling or leaving it open is likely due to exposure to moisture in the air. When the blade is unscrewed or left open, it becomes more susceptible to moisture from the environment, leading to oxidation and rust formation. By taking steps to keep the blade dry, storing it in a dry place, and using appropriate protective coatings, you can help prolong the life of your pencil sharpener blade and minimize rusting, ensuring it remains in optimal condition for years to come.