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Thursday, October 09, 2014

Bubble flare kit question for brakes line

I bought both a double flare (for brake lines, etc.) kit and a bubble
(ISO) flare kit for brake line repairs.

I can make great looking double flares on brake lines but I can't seem
to make any good bubble flares with the other flare kit.

What I'm wondering is whether getting a better branded one, like KD
(maybe Cal Van?) would make any difference?

or this one:

(these have both bubble and double flare tools and parts in it)

or perhaps I should use my double flare tool to make all the
connections except at the beginning and end of the line?

If I give up on making a good bubble flare myself, are adapters
commonly available to adapt beween a metric ISO end and a line I would
custom make myself with standard double flare fittings at the brake
cylinder, and possibly (if I replace the entire length) at the
proportioning valve?

Thanks in advance. Until the heat goes away I am not in a hurry to do
this, but I was disappointed in the bubble flare kit and it will be
returned soon.

I appreciated the advice to avoid using compression fittings, by the
way, to all of you who said to stay away from those because they
aren't made for such high pressures as in a hydraulic brake system.


  1. Most flare kits are all the same, and many made by the same mfg.

    I know...I was the VP Engineering for a auto tool maker who made these tools

    it is the correct use of them that makes the difference

  2. That explains why even the blow-mold cases of many of these are
    identical, and those that aren't look like they have identical

    I discussed bubble flares with the local auto parts stores which rent
    these kits and they say it's very difficult, if not impossible, to
    make a bubble flare with these kits. Their recommendation is to take
    it to the local NAPA dealer that has a machine shop and have the
    bubble flare made for your custom lines.

    One good thing happened today. When I took the end off one of the
    reuty lines it had--not a bubble flare--but a double flare!!!

    I can make those with no problem whatsoever, and mine look identical
    to the factory ones. So all I needed was some ends and couplers
    (double female) and I already had 25 feet of copper alloy line (a bit
    easier to bend but more costly), so I'm ready to tackle this sometime