Re: Toughest metal finish
Are you looking at something the DIY'er can do or commercial?
Birdsongs finish was supposedly very tough, but he passed and I am not sure if the process was passed on....
“When a long train of abuses and usurpations, pursuing invariably the same object evinces a design to reduce them under absolute despotism, it is their right, it is their duty to throw off such governments. …” Jefferson
We are very close to this point now.