Board logo

What flare is needed here
Slimy38 - 4/5/21 at 07:05 AM

I have this end on my brake flexi pipes;




But the rest of my system is based on the MX5 which uses SAE double flares. This is a Furore pipe with an M10 x 1.00 connector.


jollygreengiant - 4/5/21 at 07:18 AM

Single Convex or Male.


adithorp - 4/5/21 at 07:28 AM

+1 single flare.


Slimy38 - 4/5/21 at 07:30 AM

OK, I'm maybe a little confused now, everything I read on 'the internet' says single flares are a no-no on braking systems? But also the single flares I see are the same as the end of here, IE a 'female to female'? Am I looking at the wrong thing?

[Edited on 4/5/21 by Slimy38]


rusty nuts - 4/5/21 at 07:38 AM

quote:
Originally posted by Slimy38
OK, I'm maybe a little confused now, everything I read on 'the internet' says single flares are a no-no on braking systems?

[Edited on 4/5/21 by Slimy38]


Tell that to all of the car manufacturers out there! You need a single flare on that


jps - 4/5/21 at 07:41 AM

Alternatively, I would think you could use a male-to-male bulkhead connector - and therefore use female flares at either end. But then you'd be putting two joins in, where only one is really needed...

I spec'd my lines from Furore with male fittings at both ends, to avoid this. But on my brake master cylinder fittings I will need to use single flares - and indeed the OEM lines have a single flare.


Slimy38 - 4/5/21 at 07:51 AM

I've just run a 'single' flare through my flaring tool (one of the AB tools handheld ones) and got this;




It seems to fit quite comfortably in the flexi. Is this what I'm using here?


Slimy38 - 4/5/21 at 07:53 AM

This is what I found on 'the internet';




The single flare on the left is apparently the bad one, I think what I've just made is the centre one, and the one on the right is the normal double flare.


russbost - 4/5/21 at 08:15 AM

You want what your diagram shows as a bubble flare - on most machines that is the first operation & if you want a double flare then you carry out the second operation, hence why everyone is saying "single flare"

What you've shown as produced by your flaring tool is absolutely spot on


Slimy38 - 4/5/21 at 08:49 AM

quote:
Originally posted by russbost
You want what your diagram shows as a bubble flare - on most machines that is the first operation & if you want a double flare then you carry out the second operation, hence why everyone is saying "single flare"

What you've shown as produced by your flaring tool is absolutely spot on


That's great, thanks everyone for the help. I can continue now.


jester - 6/5/21 at 10:41 PM

I have not long taken all the brake pipes of my Tango jester I brought that I am rebuilding from the ground up.

I found two of the types of flares that are above on the car.

The second one & the third one.The car is based on a Mk1 Fiesta.

Are they both safe to use when I do my own flares or just stick with one type


rusty nuts - 7/5/21 at 06:02 AM

quote:
Originally posted by jester


Are they both safe to use when I do my own flares or just stick with one type


The flare that you use must be the correct type for whatever the pipe is attached to , hose/ pipe / cylinder etc. Male pipe nuts normally use a single flare ( 2nd picture) female nuts a double flare (3rd picture) , there may be exceptions
Flare like the first picture are , or should never , be used in brake systems.


Edwardo - 7/5/21 at 08:48 AM

Just to add to this - you need to make sure you have the correct 'fitting' for the connection you need to make.

There are 2 type of 'single operation' flare, the SAE single (bubble) and the DIN single.

As you can see from the image below - the fittings are different. They are both M10x1 so either will screw in ok. The DIN fitting has a square internal shoulder and a larger 'bearing face pushing behind the flat section of the copper tube.

The SAE bubble flare has a tapered face on the inside of the fitting which matches with the tapered face of the copper tube and so has much less of a flat bearing face on top of the fitting.

I'm led to believe that in reality if you use a DIN fitting on an SAE bubble flare - it just compresses the copper to a flat shoulder and seals ok.

Some people have had trouble with leaks the other way around though when using an SAE fitting on a DIN flare due to the reduced flat area on the fitting. Others have reported either fitting worked fine with eaither - so its a bit of a lottery by the sounds of it



I'll be re-doing all the brake lines on my heap in the next few weeks and will be carefully checking the fittings match the flare. I figure its just one of those things that you can cross off the list as a potential cause if you get any leaks.

Cheers
Tony


russbost - 7/5/21 at 09:08 AM

TBH if you are using copper, or even kunifer, most flares will seal with most others (not that this is something I'm recommending - always best to have the correct flare to match the other side) simply because the copper/kunifer is so soft & ductile. Steel pipes are a whole different ball game however!

If sealing stainless to stainless on braided hoses, it's particularly important to have the correct matching flare as if you try to seal a double to a double it will be sealing on a tiny ring point of contact. If you have any recently made hoses from Furoreproducts, the unions now come with a clever system that has both a single & a double flare on the end of the union, makes them a lot more versatile & more idiot proof!


coyoteboy - 7/5/21 at 10:56 AM

I found it pretty hard to buy parts that match what you expect when trying to re-do tin-top brakes - ones that are meant to be DIN being SAE looking at the geometry, some lengths being incorrect and not allowing full thread engagement when mating flares. For such a safety critical item, it's shocking that the standarads don't enforce marking of the parts to confirm what is expected.


jps - 7/5/21 at 11:45 AM

This is a great thread - as (having searched LCB high and low in the past) this is the only one i've seen that brings ALL these points together in one place.

One problem in trying to build knowledge across the range of other posts is that people sometimes refer to the 'SAE bubble flare' and the 'DIN single mushroom flare' as "single flare" - hence Slimy's confusion of " 'the internet' says single flares are a no-no on braking systems".

And then to add to what Coyoteboy and Eduardo are saying: I've found it very hard to get specifics buying online as to what unions you're actually gettting - and almost everything available seems to be SAE by default - rather than DIN - even though DIN is apparently by far the over-riding standard for many of the cars we're using as donors.