AN—or “Army-Navy”—fittings are a particularly robust type of 37-degree
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MotorTranscript
00:00 (drill whirring)
00:02 Hi, I'm Douglas Glad from Hot Rod,
00:04 and today we're going to build some AN brake line fittings.
00:07 (upbeat music)
00:09 So AN brake line fittings, why do you care?
00:15 Most cars come with what's called a coupling nut,
00:19 and that actually crushes the brake line
00:22 against the inverted flare fitting inside,
00:23 you know, whatever it is, brake caliper or master cylinder.
00:27 Problem is, the harder you tighten this,
00:30 the more likely it is to twist the tube itself.
00:33 AN brake line fittings, don't do that.
00:35 For brake line jobs, I use stainless steel brake line.
00:38 This is 3/16ths.
00:39 You want to use stainless steel because it doesn't corrode,
00:41 it's stronger, takes more pressure.
00:43 You don't want to be using aluminum line on your brakes.
00:46 So the first thing you do is you figure out
00:48 what your length's going to be,
00:49 and then you can use one of these little tiny cutters.
00:52 So the tubing cutter, basically,
00:53 you just twist the thing and tighten it at the same time
00:58 until it cuts through the pipe.
01:00 After you cut your line,
01:04 it's going to be kind of a mess at the end.
01:05 So what you need to do is chamfer the end
01:07 with a grinding wheel or a hand file,
01:10 and then take a deburring tool and deburr the end.
01:13 So this is the brake line we're going to build.
01:21 This is a good time to add the nuts and the sleeve
01:26 because once you start bending,
01:28 you're not going to be able to get these on.
01:30 The next step is to create a 37-degree double flare.
01:34 So I use this flaring tool.
01:37 It's got 37-degree 3/16ths block.
01:41 3/16ths is another word for dash three.
01:44 Then it has a die head with all the different dies
01:47 to create whatever kind of flare you want.
01:50 So next you want to square the brake line in the die.
01:54 So I usually use a little bit of anti-seize on the end of it.
01:57 And then you turn the die head
02:04 and you square the brake line
02:10 and you're ready to make your bubble flare.
02:12 Now the brake line is square in the block.
02:16 All you have to do is select the first operation,
02:19 which is a bubble flare,
02:20 which is the first half of a double flare
02:24 and pull the handle.
02:25 Okay, so this is a bubble flare.
02:33 It is the first half of a double flare.
02:36 So the next step is put it back in the block
02:40 and spin this around to the next step
02:45 and pull it again and make a double flare.
02:47 (upbeat music)
02:50 So after you make your 37-degree double flare fitting,
02:57 you slide the sleeve over it and the nut
02:59 and you're ready to attach it.
03:01 So that's it.
03:06 A-in lines don't require any thread sealer or thread tape.
03:08 All you do is tighten them up and go.
03:10 Thanks for watching.
03:11 (upbeat music)
03:14 [BLANK_AUDIO]