Further to my share of knowledge on the brake flares used on the F1 and the tools required, I thought I'd share a potential serious failure that I discovered on a 'garage serviced and maintained vehicle' recently.

Whilst changing the fuel tank cradle, more of that in another thread, I noticed a very poor condition brake hose. The ferrules had rusted away and the ends were held into the brackets on the car with jubilee clips!!

Of course, copper pipes rarely unscrew as they seize in the brake pipe fitting, no problem I thought, I'll unscrew the brake hose from the pipe, which I did.

Just about to fit the new hose and noticed a 'copper washer' on the floor. Odd thinks me, where has that come from. Further examination showed that it was the remains of the double flare on the end of said brake pipe! Obviously, I then remade the brake line as well. The cause of the flare failure? The double flare was fitted using a standard flat ended brake nut, not the one with the 90 degree countersink in the end. The result was that the double flare got crushed and when unscrewed sheared off as it was too thin.

Morale of the story, always use the correct fittings for the flare type. On the F1 there are ISO flares which require a flat ended nut and SAE double flares which MUST have the ones with the 90 degree countersink in the end to accommodate the double flare when tightened.

If I hadn't noticed the 'copper washer' the story could have been very different, wondering about the other garage fitted brake lines now !!

Previous information post - https://www.landyzone.co.uk/land-rover/brake-pipe-flares-share-of-knowledge.347073/

I've got a Sykes Pickavant vice mounted tool which can do the appropriate flares, however I have had to do some brake pipes on my BMW which are so awkwardly routed I think the design engineer responsible for them deserves a damned good beating. Consequently when I got the pipes 3/4 of the way through there was no way in hell I was taking them off to flare the second ends in the vice mounted tool and refit them. So I bought this:
https://www.ebay.co.uk/itm/272815053600


I can hands on heart say this this gives nearly as nice a flare as the Sykes Pickavant tool, and at ~£35 it may be more pricey than the likes of Nielsen's cheap and nasty flaring tools, but it is money well spent, and as such I recommend anyone who might have to use the information in Andy's cautionary tale, to buy this item.

I have the same type but for a F1 you'll need the head that does DIN flares too.

The only place I can find new Inverted flare 10mm SAE 040110 fittings which are on the FL1 where the pipe meets the flexible hose is:

https://uk.dhgate.com/product/inver...tting/397114858.html?skuid=571492067411197952

Just ordered some spares, not bad, about £8 for 10 inc postage.

Where do others get theirs from in the U.K ??

https://www.ebay.co.uk/itm/10-x-Mal...039658?hash=item3d52bbba2a:g:kiwAAOSwc7RaLcXJ

https://www.ebay.co.uk/itm/M10-x-1-...204233?hash=item48cb678449:g:q0EAAOSwKIpWCRMY

Thanks, interestingly nothing in the item title makes them stand out as different to the plain brake pipe nuts.

Out tidying workshop after yesterday's activities, thought I'd photo what I am on about above and do a simple destructive test on some scrap pipe to show the problem.

Firstly, a garage maintained vehicle brake hose retainer - vehicle has current MOT !

Now to the failed flared joint, this is what fell out of the brake hose end when unscrewed.

Ahha I hear you say, the fitter should have used an SAE 040110 type fitting, and you'd be right! Instead they used the first thing in the parts tray that has a 10mm thread.
Comparison of the 2 different 10mm brake pipe fittings, hard to see the difference, but stay with me....
Correct one for an 'inverted' or 'double' flare is on the left, the one that caused the failure is on the right.
So, to reconstruct, I took a steel brake pipe and fitted it into the right fitting and tightened it to the brake hose, all good.
When placed in the wrong fitting (look at the end of the pipe with the cone shape) the flare was badly distorted.
and the brake pipe end shape.

When the test was repeated with a copper pipe, the failure could easily be recreated.

So, if when you have placed a fitting on a brake pipe and added a double SAE flare; If it looks like the one in the next photo DON'T FIT IT!

It should look like the one below, the fitting is countersunk to allow space for the material in the double flare without crushing it to destruction.

Hopefully that all makes sense, worth convincing myself too. I hate to see a failure and not understand why it happened.
Drive and more importantly, brake - SAFELY !

As Monsieur Jeremy Clarkson once said, it's not speed that kills you, it is the rapidly coming to a stop

Nice info!

As said, wrong union used, but the mechanic probably tightened it up too much. I was once helping a (qualified, experienced) mechanic fit a copper brake pipe, and watched him honking the union up like it was steel. He told me to watch for leaks, stood on the brake pedal, and... whoosh! The joint parted. You could see the copper ‘washer’ left inside when he undid it.

For copper, snug it down by hand, then half a turn, test for leaks. Nip up 1/8 turn if needed. Better it dribbles than fails completely.

Interesting stuff. Even though a car is said to have only been garaged maintained, yer never really know who has been working on it.

Just do it effing up.. none of this 'is it tight enough' nonsense, then going back and re-tightening! Complete waste of time!! :Rolleyes:

Not sure if it’s still available but I use Kunifer nickel copper pipe for my brake lines,
It’s not as flexible as copper and not as stiff as steel but great corrosion proofing property,
Was looking at a job I did thirty years ago and the pipe Is sound with no visible deterioration,

https://www.ebay.co.uk/itm/25ft-3-1...ipe-Tube-M10-Fittings-Nuts-Ends-/152748423366

yes it’s still available

I'm using Cunifer pipe on m BMW just now, as it is more robust than copper. But the stuff I'm using is a dull browny bronzy colour, where as the pipe in the link @Europa486 posted looks like straight copper. For a fun bit of scientific testing, I decided to destructively test some Cuni flares against Copper ones. Basically I flared up a pipe end in each copper and cuni, put a female fitting in the vice and gorrilla'd it up intentionally destructively overly tight. On copper I sheared the flare off the pipe into a cper washer, on Cuni I stripped the threads.

Jayridium said:

I'm using Cunifer pipe on m BMW just now, as it is more robust than copper. But the stuff I'm using is a dull browny bronzy colour, where as the pipe in the link @Europa486 posted looks like straight copper. For a fun bit of scientific testing, I decided to destructively test some Cuni flares against Copper ones. Basically I flared up a pipe end in each copper and cuni, put a female fitting in the vice and gorrilla'd it up intentionally destructively overly tight. On copper I sheared the flare off the pipe into a cper washer, on Cuni I stripped the threads.

Click to expand...

The lesson the then is to use copper so you don't strip the thread!!

Another great thread for us enthusiasts.