[DeTomaso] BRAKE Line Flare

Sat Feb 22 17:04:44 EST 2014

Mfgrs use different line sizes on most masters to keep casual mechanics from mixing up the front & rear brake lines. In many masters, the front pistons are larger as is the reservoir, and the pressures & volume in front are meant to be different. The fittings both are (or should be) standard sizes; if this isn't the case, I'd call Hall and ask what fittings are needed. Of take the assembly to a fitting store and try some of their stock. The correct fittings should NOT need wrenches to screw in. 

Double flairs are only needed on high pressure tubing made as a sheet wrapped around a rod and brazed to make a tube. This was once known as 'Bundy-weld' and was the way brake lines were made in the U.S. starting in the early '40s. Not sure if mfgrs still use it in this century. Look closely at a cleaned bundyweld-tube and you'll see a faint copper colored line along the length.This braze line will crack if NOT doubled, while for instance, stainless tubing is nearly impossible to double-flair without cracking; the folded radius seems too tight for the harder metal and it work-hardens & splits crosswise. Bundyweld splits lengthwise.

Stock Pantera brake lines are metric size tubing and use ISO bubble-flairs. Needs a whole different failring tool (sold by K & E). Cutting off the bubble ends and trying to flair with a U.S tool, you'll probably find the metric tubing is slightly too small to be firmly held in the tool and it slides through when you apply flairing pressure. Wrapping the tubing with brass shim stock in the clamp area allows a U.S tool to hold and form U.S flairs (including double) on the metric tubing. And if you haven't messed with Pantera brake lines before, after changing ANYTHING, I would start the car and STAND on the brake pedal to try and break any weak joints under max load. Better in your garage than in heavy 80-mph traffic on the freeway! Good luck, Sean- J Deryke

-----Original Message-----
From: sean mundy <seanmundy at hotmail.com>
To: detomaso <detomaso at poca.com>
Sent: Fri, Feb 21, 2014 5:04 pm
Subject: [DeTomaso] BRAKE Line Flare

   Installing the new brake master and booster and ran into some
   problems.   Trying to verify what flares I need.
   Here is a picture of the booster from Hall.  It looks like its the same
   type booster that other owners have used.
   http://poca.com/index.php/album/mundy-sean#
   The master came with the screw in connectors but they are two different
   sizes.
   There are also different looking size connections for the front/rear.
   The rear brake connection is
   much larger than the front.  Have no idea why.
   Do both of these connections require double flares?
   Can I cut off the ends of the stock lines and flare the ends or is the
   stock brake line the wrong size?  3/16?
   The 3/16 double flare that I made looks like it would fit the front
   brake connection but the rear connection
   is just way too big.
   Thanks for any help. Sean

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-------------- next part --------------
   Mfgrs use different line sizes on most masters to keep casual mechanics
   from mixing up the front & rear brake lines. In many masters, the front
   pistons are larger as is the reservoir, and the pressures & volume in
   front are meant to be different. The fittings both are (or should be)
   standard sizes; if this isn't the case, I'd call Hall and ask what
   fittings are needed. Of take the assembly to a fitting store and try
   some of their stock. The correct fittings should NOT need wrenches to
   screw in.
   Double flairs are only needed on high pressure tubing made as a sheet
   wrapped around a rod and brazed to make a tube. This was once known as
   'Bundy-weld' and was the way brake lines were made in the U.S. starting
   in the early '40s. Not sure if mfgrs still use it in this century. Look
   closely at a cleaned bundyweld-tube and you'll see a faint copper
   colored line along the length.This braze line will crack if NOT
   doubled, while for instance, stainless tubing is nearly impossible to
   double-flair without cracking; the folded radius seems too tight for
   the harder metal and it work-hardens & splits crosswise. Bundyweld
   splits lengthwise.
   Stock Pantera brake lines are metric size tubing and use ISO
   bubble-flairs. Needs a whole different failring tool (sold by K & E).
   Cutting off the bubble ends and trying to flair with a U.S tool, you'll
   probably find the metric tubing is slightly too small to be firmly held
   in the tool and it slides through when you apply flairing pressure.
   Wrapping the tubing with brass shim stock in the clamp area allows a
   U.S tool to hold and form U.S flairs (including double) on the metric
   tubing. And if you haven't messed with Pantera brake lines before,
   after changing ANYTHING, I would start the car and STAND on the brake
   pedal to try and break any weak joints under max load. Better in your
   garage than in heavy 80-mph traffic on the freeway! Good luck, Sean- J
   Deryke

   -----Original Message-----
   From: sean mundy <seanmundy at hotmail.com>
   To: detomaso <detomaso at poca.com>
   Sent: Fri, Feb 21, 2014 5:04 pm
   Subject: [DeTomaso] BRAKE Line Flare
   Installing the new brake master and booster and ran into some
   problems.   Trying to verify what flares I need.
   Here is a picture of the booster from Hall.  It looks like its the same
   type booster that other owners have used.
   [1]http://poca.com/index.php/album/mundy-sean#
   The master came with the screw in connectors but they are two different
   sizes.
   There are also different looking size connections for the front/rear.
   The rear brake connection is
   much larger than the front.  Have no idea why.
   Do both of these connections require double flares?
   Can I cut off the ends of the stock lines and flare the ends or is the
   stock brake line the wrong size?  3/16?
   The 3/16 double flare that I made looks like it would fit the front
   brake connection but the rear connection
   is just way too big.
   Thanks for any help. Sean

_______________________________________________

Detomaso Forum Managed by POCA

DeTomaso mailing list
[2]DeTomaso at poca.com
[3]http://poca.com/mailman/listinfo/detomaso_poca.com

References

   1. http://poca.com/index.php/album/mundy-sean
   2. mailto:DeTomaso at poca.com
   3. http://poca.com/mailman/listinfo/detomaso_poca.com