Brake Line Flaring

do you have a good double inverted flare tool and a good tubing cutter?

Classic Tube in NY did mine. I sent them regular brake lines that I bent to shape. They sent me back stainless lines bent, flared and ready to install. Cost was just under 300.

Fwiw one time I used transmission line for oil lines on a shovelhead, anyway I used a bit of heat before I flared and it made a huge difference. I wonder if heat would be a no no on brake lines?

Falcon79 said:

Hey guys,

I am trying to finish up adding four wheel disc brakes on my 1968 coupe. The one thing holding me back is I need to fabricate a few brake lines and I can't get good flares with any of the tools I've bought. I'm through throwing money at tools and I want to pay someone to do it. If I bring the lines and fittings to a brake shop, will they add the flares for me? Does anyone know how much it would cost?

If anyone has any info on this and can keep me from looking like an idiot and getting hosed on the price, I would appreciate it.

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Are you using stainless brake tubing? Stainless works best with a single flare. Regular steel tubing needs a double flare. I have a quality flaring tool and it makes perfect flares.

If you decide to add some heat, I have a MAPP Gas tank you can borrow.

IMO you can hardly make quality flares with the U-like flaring tool, no matter if it is HF or Snapon brand - 95% are the same crappy design, for 10 sizes you will never use. Maybe snapon is made from a better material.

I would pick tool that has precisely made clamps and flaring tip that keeps centered as you tightening the clamp, e.g.
Bernert - BeKaS s.r.o - brzdové trubky, brzdové hadice, koncovky brzdového potrubí, odvzdu??ovací ?rouby, brzdové oblo?ení, brzdové ?elisti, brzdové kotou?e, p?íslu?enství k brzdám

Eastwood sells also a good one - a copy of a Sealy brand and is not very expensive. Ridgid's design looks promising too.

I gotta ask, do the flares you're making work, but just don't look good to you?

I use the standard el-cheapo brand IF tool, and it makes a round, symmetrical working flare every time.

I do these things first though

after cutting the brake line I take a oversized drill bit in a drill to get rid of the burr leftover from the cut. I'll even run a bit by finger inside the line to be sure that tube is as round as it's supposed to be.

I make sure that the cut off end is as perpendicular in the tool as possible.

On the first flare, I re check the die to make sure the stupid thing is not starting crooked. After preloading it, I typically might tweak the angle.
After that first bubble is made, I know how the second flare will look based on how uniform it is. But having used the same tool for several cars now, the bubble has to be seriously F'd for it not to seal after the last flare is made.

And definitely, if the lines are SS, use one 37 degree flare w/ the goofy adapters or the line will fracture or break.

Just my .02

All tools I have seen had the end tip guide's outer diameter 0.5mm smaller than tube's ID. Your is different?
Most likely designed for thick wall 3/16 tubing, yet all the steel tubing for custom flaring are thin-wall, two layer because it is much easier to bend.
Due to this the end tip tends to go off-center as you tightening the tool. The bubble flare is round, yet if it is off by several tenths of mm, it will leak - same if you do SAE flare in the next step. You have to have a precise feel to operate this tool. It is not like cut and deburr the tubing, place it in the clamps, tighten and voila you end up with a sealing flare.
Deburring with a drill bit is OK yet won't help keeping the tip centered.
There are clamps too that keep the tubing firmly without biting to it. Due to this, the rust will not develop under the end fittings - the worst possible place.
The other story is if you deal with copper tubing. If imperfect it is easier to shape the flare as the end fitting is tightened because copper is softer.