View Full Version : We gotta talk about this again...

01-15-2007, 01:33 PM
Double flaring a brake line...
I'm aware that there is all you need at the local NAPA store. However, I have a unique situation right now, in that, I'm installing a metric threaded master cylinder and an SAE threaded Combo Valve. So, I have to customize 2 pipes.
I have 3 similar tools to make double flares, but have NEVER been able to make a usable one. In the process of trying, most of the dies that are required to do the first crimp, break fairly easily. The pin on the die is much smaller than the ID of the pipe and the screw clamp will inevitably crush it at a cockeyed angle, snapping off the pin. You can't replace just one die, but have to buy all the ones you'll never use too.
Just yesterday, I spent a couple hours, using different techniques, all to no avail (and broke another die).
I've been told there are metric to SAE adapters, but won't find out until tomorrow, when I pick up the MC.
Any ideas? thx

John Kirchhoff
01-15-2007, 08:04 PM
My local NAPA dealer has a whole display case full of brake line fittings. Everything from brass flare fittings to steel compression fittings for non-flared lines. A good while back I was looking through them and I THINK I saw metric to SAE fittings. Not 100% absolutely sure, but I seem to remember seeing them. The display case must have had 25 drawers all with different sorts of brake line fittings, so I'd sure think there's something that would work.

01-15-2007, 08:28 PM
Don't know about the adapters, but the key to not breaking the little tit off the flaring die is to have the cleanest, squarest cut possible on your brake line. Buy a new, GOOD tubing cutter, and if the cut doesn't look perfect don't be afraid to dress it with a flat file and/or clean up the inside of the line carefully with a drill bit. A good tubing cutter should actually have a reaming blade that can be used on the larger tubing sizes.

You'll still break the little 3/16" one eventually; there's no hope for that one.

good luck,


55 Commander Starlight