I have an old-school brake line flaring tool that I've reluctantly used what seems like 1,001 times to flare 3/16 steel brake line. It's the inexpensive one available at the parts store with the wing ...

Flaring metal brake lines and metal fuel lines (or transmission lines) is something of an art when using the most common type of double flaring tool. We're talking about the mass-produced double flare ...