Feel free to check my other Rust Removal videos on my YouTube channel
Below you can see the before and after results after 1 night of electrolysis de-rusting, the duration depends on the level of rust, for light rust a few hours is more then enough, for heavy rust over night or more might be more suitable. After the electrolysis is done a bath of vinegar is recommended for the de-rusted part, makes it easier to clean all the electrolysis left over residue. The adjustable spanner below was covered with rust over 4 years.
After the de-rusting process is complete I would recommend to cover the part with some lubricating oil, alternatively spray paint it after the cleaning as it will oxidize very quickly if not treated.