Lessons learned - Wheel cylinders and sealing stainless lines
Several years ago I plumbed my entire braking system with SS tubing - never again. I have good quality tools but the stainless was difficult to get a good flare on, was harder to bend and everything leaked. I went through the tighten/loosen/tighten process several times and could never get it 100%. Wish I would have found out about copper sealing washers when I was going through such a frustrating process. Good to hear they work. Frankly, they should not be necessary though, the flare is supposed to be the seal. Stainless is just too hard of a material to form.
I use coated steel line now. 100X easier to work with and doesn't corrode.