If you aren't sure what black oxide coating is, it's the process of introducing nitrates, sodium hydroxide, and other chemicals to exposed metal. This process creates a black substance along the outside of the metal piece which protects better than paint and can help reduce the amount of time it takes for something to rust.
This process is totally doable by yourself! With smaller items, you can easily give them a quick black oxide coating. Using the ingredients in the video, soak your small items generously after you have thoroughly cleaned them.
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The soaking time can differ for different items but the main goal is that you don't want to be able to rub off the coating. Once that coating is solidified then you are going to need some penetrating oil that gets through the coating and helps further protect the metal underneath.
While black oxide coating helps protect metal, it doesn't stop rusting and shouldn't be done on larger projects without the proper safety materials. This is where it would be better to find a company that can take on the task of safely coating your items. Otherwise, stick to the small stuff and you'll be just fine.
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