Question on flaring for AN fittings

[richtersand]

Hey guys, I'm a little confused so looking for guidance on 37 degree AN fittings. I have read that you never want a single flare in a high pressure brake line, so do double flares. But then, when I research double flares for AN fittings, I see a lot of people saying only use single flares for AN fittings. Is it true that you should only use single flares for AN fittings? If so, what should I make of the many people saying never use a single flare on a brake line? Any thoughts/guidance would be much appreciated!

[Jeff Kleiner]

AN flares are 37 degrees; automotive brake line SAE inverted (double) flares are 45 degrees. They are NOT interchangeable or compatible with one another.

Jeff

[richtersand]

AN flares are 37 degrees; automotive brake line SAE inverted (double) flares are 45 degrees. They are NOT interchangeable or compatible with one another.

Jeff

Thanks Jeff. I got that, sorry if my question was convoluted. I am asking whether 37 degree AN fittings require single or double flares? I see brake applications need the double flares, but I’m also seeing AN fittings don’t use double flares??

[Jryasko]

Single flare for the AN fitting. The AN usually has a ferrule behind the flare that has the 37 degree angle on it as well, the nut slips over this and pilots the ferrule and the ferrule beefs up the back of the tube.

[richtersand]

Single flare for the AN fitting. The AN usually has a ferrule behind the flare that has the 37 degree angle on it as well, the nut slips over this and pilots the ferrule and the ferrule beefs up the back of the tube.

Thanks for the response. It all makes sense now, planning single flares for the fuel lines and double flares for the brake lines.

[edwardb]

Thanks for the response. It all makes sense now, planning single flares for the fuel lines and double flares for the brake lines.

Count me as slightly confused. Double flares for brake lines is correct. But why asking about AN fittings and 37 degrees for brakes? Doing something different? The brake components provided with the kit are all 45 degree fittings, which is typical. Can't use with 37 degree flares.

[richtersand]

Count me as slightly confused. Double flares for brake lines is correct. But why asking about AN fittings and 37 degrees for brakes? Doing something different? The brake components provided with the kit are all 45 degree fittings, which is typical. Can't use with 37 degree flares.

Sorry, I am not communicating very well because I'm learning as I go. Part of the fun of the project! I think the fittings world is starting to make more sense to me now and I'm totally in agreement with you Paul. Funny timing because I'm going to your 20th anniversary build thread now to see the fuel line routing...

[Jim Stabe]

Thanks for the response. It all makes sense now, planning single flares for the fuel lines and double flares for the brake lines.

If you decide to use double flare for brakes, the fittings have to be 45* and the flares have to be made a with 45* tool and they don't use a ferrule. If you decide on AN lines you need to make 37* single flares on the tubes, use a 37* ferrule and AN tube nuts and also use 37* fittings. Don't mix them up.

[richtersand]

If you decide to use double flare for brakes, the fittings have to be 45* and the flares have to be made a with 45* tool and they don't use a ferrule. If you decide on AN lines you need to make 37* single flares on the tubes, use a 37* ferrule and AN tube nuts and also use 37* fittings. Don't mix them up.

Roger that, thanks for the help.