Another knife I made from a file

Mandatory finished product first

Readying the file to be annealed (soften the hard steel so it can be shaped) in fire

The file has been brought to critical temperature and now I'll let it cool slowly in the ashes

After cooling off and checking that it's still straight, I'll clean it up and start cutting it to the approximate final shape

After spending some time at the belt sander it starts looking like a proper knife

More filing and sanding later, it starts to shine. Also in the picture, the tail of the file, which will become a bottle opener.

Time for hardening the steel again. This time I'll bring it to critical temperature and cool it off quickly in hot oil (that's called "quenching", if you're a terminology nerd). This will make the little atoms line up in a specific way that makes the steel very hard. Later, I'll soften it a bit in a process called tempering, so it regains some flexibility.

Next, make the rest of the knife.

Glamour shot

Yeah baby, show me what you got! ;)

And a little video for you knife nerds.