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Tool for making bubble flares on brake lines

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Sarastro

Sarastro

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Does anyone know of a good, not-too-expensive tool for making bubble flares on brake lines? I'd like to be able to fabricate my own brake lines. I bought one highly recommended tool, Performance Tool 80670, and it turned out to be complete junk.

Ideally, I'd like a tool that makes both Girling style bubble flares for LBCs and more modern SAE double flares in 3/16" line. But I'll be satisfied if it only does the latter.
 
A secret I discovered is to be selective about what material you try to use. The pre-terminated lines at the parts store are hardened and very difficult to flare. I tried several different flaring tools, even the expensive Snap-On tool I borrowed from a local professional didn't work well at all (although I did finally manage to get a serviceable bubble on about my tenth try).

However, if you buy coiled brake line, it comes annealed, which makes it much easier to flare. And of course Cunifer (copper/nickle alloy) is easier yet.

Other tricks include making sure the cut end of the line is square, then cutting a slight chamfer on it. A good lubricant will help, too.
 
Going around the I.D. of the end you're about to flare with a round "Swiss" file (small files in sets), to eliminate any stress risers helps A LOT.
 
You need to purchase a flaring tool the you can fit into a vise. Eastwood has one in their catalog. You will spend some $$'s on it, but it will last a life time. I had to use my small flaring tool on a Nardi/Fiat this week-end in a tight spot, but prefer that large unit. Never heard of hardend flairs...not sure that they would seat properly.
Of coarse, make sure that the end is square, and use a reamer to clean out the inside of the pipe before flairing.
Cheers,
D.
 
For a quality made double flare kit look at Mastercool#70092. List $90.68 Sale price $74.25 Comes with a top shelf $25.00 tubing cutter also. 90% of all the other flare kits are Chinese junk that dont hold the tubing and make crooked flares,if you do get the tool to work.I have sold hundreds of these and my customers are happy.
 
Thanks for the suggestions.

Someone else told me about chamfering the edge of the tube, which I had neglected to do, and of course reaming the inside is clearly necessary. I have been using the Cunifer tubing, and after a couple more tries, got a borderline decent flare. I'm still not happy with it, though.

I'll look into the Eastwood and Mastercool tools.
 
I do not recommend "chafering" the edge, unless you have a way of making the chaf at the same degree all the way around the tubing.
Cheers,
D.
 
I don't think you need a big chamfer, but a slight dressing with a small, fine file before going to work with the flaring tool helps a lot.

I've also found that lubricating the tool and the pipe, with brake fluid preferably, helps the job tremendously, and cunifer makes a very nice job.
 
Roger said:
...but a slight dressing with a small, fine file before going to work with the flaring tool helps a lot.

I've also found that lubricating the tool and the pipe, with brake fluid preferably, helps the job tremendously, and cunifer makes a very nice job.
Click to expand...
:iagree: My findings have been the same.

I bought a cheap tool at Princess Auto last year when I was in a pinch and by making sure that the end was square, lighty dressing the pipe and a small amount of grease, I was able to consistently make bubble flare fittings that did not leak.
 
Grantura_MKI said:
Purchase a quality tool, and you will not need to do all of this extra work.
Cheers,
D.
Click to expand...

Even the best quality flaring tool won't compensate for off-square cuts, burrs, etc. Even the best tubing cutters can close up the hole a bit, too.
 
Hi Roger,
Please read my previous posts. I restore English vehicles for a living. The last car that I re-piped was a Lotus TC Special fitted with twin servos, etc. Many feet of pipe and flaring done. After filling with fluid and proper bleeding there were no leaks.
Cheers,
D.
 
Grantura_MKI said:
Hi Roger,
Please read my previous posts. I restore English vehicles for a living. The last car that I re-piped was a Lotus TC Special fitted with twin servos, etc. Many feet of pipe and flaring done. After filling with fluid and proper bleeding there were no leaks.
Cheers,
D.
Click to expand...

I don't doubt your credentials, but are you telling me that what I've written is wrong?
Besides what you may purchase as a professional restorer, will get amortised over many vehicles and be well beyond the budget of many here.
I recently re-piped my Lotus TC, but added lightness by dumping the servos and replacing the master cylinder. Less pipes, less weight, no leaks either.
 
I got one a couple of years ago, seems like it was around $60. Can't remember make but it works well. You must make sure you cut the tubing straight or forget it. I use a cutoff wheel on air tool clean up the end before flaring. Leave the tubing little long in case you need to redo the end. Like Randall said, the coiled tubing is easier to flare. I tend to use the 4 ft straight lines to keep the lines looking straight, can't make them look right otherwise.

Marv
 
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