The Stovebolt Site Forums The Shop Area Driveline Flaring brake lines how-to

I've notice several posts asking about flaring brake lines. I just happen to have to do some today, and thought I'd post some pix to show how it's done. First, the tools ,mines a professional kit, but the kits fom the flaps work similar http://rides.webshots.com/photo/2188171820092261295sexvyb
first operation is reaming a bevel on the end of the tube http://rides.webshots.com/photo/2034722880092261295VJsClF
next is clamping in the appropriate die, note that the end of the line is flush with the die surface
http://rides.webshots.com/photo/2909677320092261295nflRjW then the upsetting die is used to start the flare by foling over the ned of the line http://rides.webshots.com/photo/2794117050092261295mYQGnS
after upsetting die, the line is now partially folded in on itself, creating the double wall of the flare now the cone die is used to finish the flare, the folded part of the line is forced into the flare
finished flare http://rides.webshots.com/photo/2971355310092261295HdcWDXhttp://rides.webshots.com/photo/2763082590092261295KySWjB
I do appologize if my post is a little sloppy, I'm still learning how to do picture posting.

Sweet.. that is how Rusty Rod does it too.. but Rusty uses an elcheapo kit.... does everything the pro kit does, except to get the TIGHT close bends!!

my 50 dollar kit from sears did alright except the flare seemed to be al little off center. i thought it was kind of weird. funny thing was that the clamp broke on the very last flare i had to do. guess i just got lucky.

Thanks for the info, Bill. I've attempting flaring only twice. The first time, I failed to move the connections to the ends before bending, causing them to jig-lock mid-length. The second time, I made a wonderful line (with fittings on the ends!) but sadly, it was a mirror image of what I needed. I learned that you can't simply twist the line into submission.

I tend to make lots of "practice parts."

Bill

I have found that the cheaper kit does not have sufficient clamping force to keep the line from backing out during the process. I had to use a large vice to enhance the clamping force. I would not buy the cheap kit again.


By the way, the cheap version does not look like the real thing at all.

i took mine to a local brake shop
they have a very expensive flairing tool
it cost me $5 end
i pre bent all lines and took the whole truck's set down and had it all done in 15 minutes
my all new installation was a snap.

I have an expensive flaring tool which I got in the late 1960's. I replaced all of my brake and fuel lines in the early 70's using this tool. I used Bundiflex tubing and got excellent results. All flares were 100% perfect. Fast forward to 2006....I needed to flare a new fuel line last month so out came the expensive tool which had worked so well years ago. Trying to flare modern day flex line was impossible. The tube just slipped down the clamp as I tried over and over again to get the first flare. Then it dawned on me that the tube they make nowadays is cheap and thinner walled than the old stuff so it just slips past the clamping device. I hate to throw the tool out but it is useless with the newer tubing.
Just thought I'd add my experience so I might save someone else a lot of frustration. Guess I need to buy a new expensive flaring tool!

On my old flaring tool I was able to remove some material in order to get it to clamp down more.You might try it before tossing it-the way I looked @it I had nothing to lose. I had a similar problem using copper tubing on the water line to the dishwasher in my house-the tubing collapses instead of the comp fitting. I remedied it by buying a $10 flexhose. Brian

I wonder if there is a "metric" measurement on the new tubing?
Ter

Yeah Brian, I did grind off a little of the clamp at the meeting surfaces but it still did not work. And I was afraid if I ground down too much I would end up with pinches on either side of the tube or worse, the tube would oval out. But as you said, nothing to loose in trying it again.

My $3.00 retool tube flarer and my $20.00 FLAPS tubing bender work pretty good.

I'm better at flaring than bending, but the job gets done.

Ter, there are metric brake lines, but they are used on modern vehicles and have a different type flare. It's called an ISO or "bubble" flare. Not compatible with the older style brake components.
By the way, there's nothing wrong with using an inexpesive flaring tool. I have an old KD kit that does very well, though it does require some extra clamping force to keep the line from slipping.

About 15 years ago, when I was 17, I bought the mid-grade flare kit from Snap On. The kit still sells for right around $100; hasn't gone up in price much at all since I got mine.
It comes with a very nice tubing cutter, and directions. It is because of this kit that I enjoy doing brake lines so much! Really. I do.
I've never had a flare split or crack, and they've always turned out well.
I also have the expensive kit shown in the first post. It's nice, but the simple Snap-on one does the job well for me, and I typically use it.

Essential for the job is a good tubing cutter. You MUST have a nice square cut on the end. I also added a set of very small files to de-burr the ends (this includes round and tapered needle files to get inside the tubing).
I also have one $65 tubing bender that will bend 3/8-inch line into a radius the size of a quarter. NOTHING can beat it for making good, easy bends for a factory fit and finish. I need to invest in two more of those; 1/4 inch and 1/2-inch.

If you buy cheap tubing tools from NAPA or other places, you'll always be frustrated. This is one of those jobs where good tools make or break (brake?) the job.

Brad

This is the flare tool that I used in the demonstation. It's a Snap-On/Blue point. It is a little expensive for the average 'Bolter. I use it in my work as it does any flare for late model cars. http://buy1.snapon.com/catalog/item...6&store=snapon-store&dir=catalog This one is the type that most of you will use. It's made by KD, and can be found at the flaps for about $20. It does a good job, but requres practice and patience to get good flares. http://www.kd-tools.com/2199.htm

you can try running a tap through the hole to roughten it up a bit more to grab the line.I was having the same problem with the line sliding throught, tapping the block helps, the real fix was i found a snap-on flare block and have no problems even with 5/16 line..

I purchased a "Lisle #31310" flairing tool last week and attempted to do my rear axle brake line. I practiced on some old original lines with limited success. The old lines wanted to split, but the new line turned out OK. What seemed to help was to use pliers to hold the adapter and cone from turning in the brake line during the process. The new brake line seemed to be "softer"? Just my 2cents.

I must be doing something wrong, I've bent up two trucks worth of lines, including fuel with my cheapy Lisle one and didn't have any problems. Maybe a half dozen redos. I cut the tubing with a tube cutter, deburred, filed it so it's perfectly square with a slight chamfer,clamped the whole shebang in a big vise, made sure the die tip was well lubed with brake fluid, and slowly formed the flare making sure the die remained square. So far after about 5,000 miles, no leaks.

Bob

Alright, Denny! Your flares look just as good as the factory done ones, maybe even a little better. Just don't forget to put the fittings on before you flare.

I checked out Fedhills website. The tech page has a lot of info on nuts and fittings.
http://www.fedhillusa.com/?page=tech2

OK Denny cough it up!!!
We want details on this Limy tool, where you got it and how much it cost! I ordered that $100 kit from Snap on the other day. However from all I have read it probably won't work any better than my Home Depot job.

Thanks Denny, this has been a problem for us for some time. Seems you've found the right piece of equipment. Thanks for all the info!

Denatured alcohol would be a better choice for cleaning, most Brakekleen type products are petroleum based solvents. Brian

brjr51 - Hi Bob,

Which Lisle flaring tool do you use? The one for around $50 or the one in the orange case for around $115.

Thanks,

Dennis,
I use the cheaper one I got from Farm & Fleet. I've found the secret to be a square cut on the tube, making sure the die starts and remains square to the tube through the forming, and some brake fluid for lube.
The problems arise when the die starts to angle as it's being tightened. I tighten it very slowly and keep a close eye on it. If it even looks like it's starting to cock, I stop and correct it.
Mind you, this tool only works on the mild steel line, I wouldn't even think of trying stainless.

Bob

all chlorinated solvents are nasty stuff. for the environment and for you. many states have some type of ban in place.

I used to worry about contamination & cleaned brake things w/denatured alcohol, haven't really given a darn in years(can't make money doing that)& I just use Brakleen now. I have seen many, many cars where power steering fluid or ATF or even motor oil was put into the brake system-I just replaced the master(always) & calipers maybe, bleed system w/brake fluid. One shop had a pressure bleeder, worked great but fits very few cars nowadays. You can't clean every line, nook & cranny, ya cannot make a living as a tech doing that. They always seemed to be OK. Easy to tell if too much petroleum has messed w/the system, the little gasket on the master cyl cap will be about 2x its normal size. I got no clue as to what is in your brand of Brakleen, I just assumed it is petro based, some around here is even diesel fuel(Autozone brand)w/a propellant!!! Brian

Thanks Bob,

I was at Sears last night and all they had was a double flaring tool for about $25. I am kind of scared of a cheap tool. Searsman said if I didn't like it, bring it back. I told him I would think about it and left.

So, I am thinking of the Lisle tool. But am unsure if anyone sells the tool in the Dallas area or if I should order it from them off the internet. I don't care for a $500 tool. I will probably only do my two trucks and believe it would be cheaper to get the pre-bent lines from one of the venders. Well, then there are the gas and vacumn lines. HUMMMMM

Time will tell.