I don't necessarily think the 45 degree double flare is the work of satan--it
functions just fine. But it takes a lot of practice and rejects to get it to
work well, and it's five times the effort of a single 37 degree flare (install
in die with just the right amount of tube extending past the edge, insert end
die and form bubble, find that the tube has slipped down, cut it off and try
again, get a nice bubble, squash it in, discover that you forgot to put the
nut on the second time, try to slide it all the way down the tube, give up on
that and cut off beautiful new flare, lather, rinse, repeat), especially with
the cute sliding block die setup that Aircraft Spruce sells with thier least
expensive tool (the one I use and like a lot). So why bother? Most people say
the 37 degree single flare is superior, I think they look very spiffy with the
818/819 bits, and they work perfectly every time. I've had a lot of 45 degree
double flares leak initially requiring additional tightening or rework. Never
once with a 37 degree single.
From: Fubog1@aol.com [mailto:Fubog1@aol.com]
Sent: Wed 1/10/2007 11:47 AM
To: firstname.lastname@example.org; email@example.com
Cc: firstname.lastname@example.org; Bill Babcock; email@example.com
Subject: Re: [Fot] Source needed for single-flare brake lines
OK all, I have this here crow in my hand & I'm fixing to bite his head of
iff'n I have to...
Reference DOT FAA "Aircraft Inspection & Repair", calls out double flare 37
degree on soft material, single flare on hard.
Carroll Smith takes it a step further on page #207 in "screw to win" & places
people like me under the "fool" category... (I've been told that before) &
advises NOT to use the AN818/9 to adapt 45 JIC to 37 AN, but this is referring
to a SINGLE flare end. I would suggest that the double flare, due to the extra
thickness, likely allows more deformation so as to provide a leakproof seal?
Also I consider automotive grade bundy tube to be fairly "soft" until it is
When I spoke with Pegasus tech today, I was very clear with my question & the
reply was that this is completely acceptable. Those who know me know that I
try to do my best & I truly have not had problems using this method for many
years, but I'll admit that just because something works doesn't necessarily
mean that it's "right".
Does anybody else do this?
All input is appreciated,
Fot mailing list