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A bit of Flair!

Making your own brake pipes isn't difficult with a little practice and a flaring kit.


Favourite MOT fail is excessive corrosion on the steel brake pipes. Unions on the end also have a habit of seizing to the pipe, so when you come to undo them to get the calliper off for overhaul or something, you end up twisting the pipe in half.

Not too expensive to get your local motor-factors to make you a new one; but you usually need one when they are shut. If you have to do the whole system, though, could prove pricey.

Pipe and unions are actually quite cheap, and after a couple of practice goes, it's an easy job to master.

I had to replace the four hard hosed between the callipers and flexi-hoses on Jaqui, so while I was at it, I took some 'photo's to show how it's done.

Techniques used though are pretty much universal and can be used to make up pipes for rear disks, front or rear drums, or any of the other plumbing in the brake system, between the master cylinder and say ABS control block, or inertial valve and then along the chassis rails to the flex hoses. And it's not just useful for brake systems, either; same technique, and often the same unions and fittings are used for clutch master and slave cylinder plumbing, and in larger bore, often for power steering pipes; transmission cooler pipes, and some-times coolant plumbing.

Now, I had to replace all four hard hoses on Jaqui's hubs, between the callipers and the Flex-hoses for the MOT; it's one of those 'niggly' MOT fails, 'excessive corrosion on brake pipes'. Looking for other parts I needed, I thought I'd just see how much ready made hoses were on Cradock's web-site, but they didn't list the pipes individually, they just had a complete car kit; Which I thought about, wondering whether it might be as well to do the whole lot and be done with it. But, kit was about 80, so I didn't bother.

Hard hose from my local motor factors is about  2 a meter, so do the whole car would have taken about 15 or 30 worth of pipe. The unions at the ends, can often be 'salvaged' off the old pipes, but, hey lets push the boat out here, and get new ones, there's about thirty of them, at less about 20p each! so in total, maybe another 10. So, give yourself an extra roll of pipe for practice and mistakes, and if you had a whole car to do, the cost of the flaring kit would just about pay for itself against buying a kit.

More usefully though, having a kit, some pipe, a few spare unions and the know-how to put them together, can save an amateur mechanic an awful lot of hassle; Because its one of those annoying things you often don't expect to have to replace. It's that inextricable Murphey's Law, again!

Any way, doing the calliper pipes is a pretty good example; as these are normally the most awkward, tending to be short, needing to be carefully routed, and bent into dang awkward shapes!  So, lets get on with it shall we?

Part 1 - Equipment & Materials

Step 1 - Familiarise yourself with the Kit.

Any way, first thing you need is a flaring kit. I got this one a couple of years ago, from Machine Mart , for I think, about 20. There's a couple in the catalogue, this is the more expensive of them, though its only a couple of quid, and the main difference is that this one has a pipe cutter in it. That's the red thing in the top right hand corner of the box.

This is a useful gadget! It cuts without crushing or making filings; which is quite important if you think about it; last thing you want to be doing is hack sawing through a piece of brake pipe and leaving metal filings inside it to be flushed into you brake cylinders to block ports or cut seals up! Not all that helpful to try cutting them with a pair of pliers or cutters that will crush and close the ends up either, for reasons you'll understand better in a minute.

So working round the box from the cutter, in a clock-wise direction; Next, we have big silver claw type thing that looks a bit like a nut-cracker with a screw through the middle, that is the press.

Beneath the press, at the front of the box, in two rows either side if the handle, we have seven small round black things; these are 'dies', they are pressed into the end of the pipe by the press, and are the things that actually shape the metal.

There are seven of them, for seven different gauges of pipe. For brake pipes, we'll only use the smallest, 1/4" 'bore'. Make sure you don't loose them, those are the important bits!

Coming back up, then, thing right in the middle two big wing nits on it, that's the clamp. This holds the end of the pipe tight, and is gripped by the claws of the press, while it presses a die into the end of the pipe.


Step 2 - Familiarise yourself with the Materials

In the pic left, we have the pipe in the coil round the outside, and the fittings in the middle; Pic Right, we have a close up of the fittings

Pipe itself needs no further introduction or explanation, fittings a little more so; Male unions look like a bolt with a hole down the middle, female ones look like a dome nut with a a hole in them; longer male fittings are used to make an inline connection with a female, the shorter male fittings are the ones that go into the brake callipers or hoses,; you can use the long males in hoses or callipers, but there's more thread exposed. Check what length of male you have on your old pipe or try before you make up to see which gives best fit for your particular application.

One thing I haven't shown, mainly because I didn't have any, are 'special' fittings, such as T-Pieces. A T-Piece is commonly used at the rear of the car to take the single pipe from the master cylinder and direct it out in two directions towards each rear wheel brake. Tends to be a block of brass, in a T-shape strangely enough, with three ports in it to take male unions; sometimes has a bracket so it can be bolted to the chassis or axle. Other 'special fittings' are available for various jobs; but usually work the same way, and take a standard 'line union'.

Part 2 - Flaring an End

Step 1 - Cutting the pipe

This may or may not be necessary, but..... if you don't have a nice neat square end on the pipe to begin with, you wont get a nice neat square flare in it when you have finished, so if you are using pipe that is new or been sat around, worth taking a bit off the end, just to dress it and give yourself a good end to work too.

As mentioned, a proper pipe cutting tool is by far the best and safest way to do this, to avoid getting swarf in the hole and to be sure that the end is square.

Process is pretty simple, you pit the pipe into the V of the two rollers, then screw the clamp so that the blade just rests against the pipe, then turn the cutter around the pipe.

Don't worry if you don't cut through straight away, its a case of minimum pressure so you don't crush the pipe while cutting.

Tighten the screw a tad, like maybe 1/16th of a turn, and give it another turn around the pipe, repeating until the pipe is through all the way around.

Shouldn't take long, and you will have a nice neat end to work with.

Step 2 - Straighten up the end

Your pipe will have come off a coil, and the end is most likely not straight

It helps if the end is good and straight for a portion maybe 1-1 1/2" beyond the end, as this is where the union will have to slide and turn on the pipe and where the flare will be made.

The clamp-die can be used to straighten the pipe, quite neatly;  simply put the pipe into the clamp  with the flat edge towards the end you are going to work, the chamfered end away from it.

Then working from the pipe end,  a little less inside the clamp face, clamp it in place then undo, and work the clamp down the pipe half a clamps width at a time.

But turn the pipe in the clamp as you go, to avoid the pipe taking on a new curve, or getting a 'nip ridge'. Maybe three or four clamps, over two or three clamp widths, should nicely take any bow out of that first section of pipe.

This little bit of preparation helps insure that the end of the pipe when you put the press die on the end of it is as close to square to the clamp die as you can get and the two will press together nice and evenly giving you a good flare, without one side being more flared than the other, which can result in a poor seal in the union.

Step 3 - Put Union on Pipe

Your pipe will have two ends, and this isn't strictly necessary, IF you are doing the first end.........

BUT, you CAN'T fit a nipple over a flared pipe end, and  Murphey's Law, WILL come into play, and when you are working on your last bit of pipe and CANT afford to take 3/4" off the end and make a new end you WILL do the second end leaving one or both nipples off!

So get into the habit of putting them on before you flare, which ever end of the pipe you are working, and checking you have them on the right way round!

STUPID thing to have to say, but one of those annoying 'silly' mistakes that are oft made!

Union goes on BEFORE flaring; thread pointing at end you are about to work on. (Don't let it fall off the other end, either! Bit of insulation tape can help here)

Step 4- Setting the Dies

This is the 'awkward' bit, and where it starts to take a bit of a practiced hand; if you have instructions with your kit, you may be lucky enough to have a chart that tells you how much pipe you need to have sticking out the top of the clamp-die to make a decent flare.

RULE OF THUMB if you don't, is you need ABOUT as much length sticking out as the pipe's diameter, so if you are using 1/4" gauge pipe, which is what I have here, you need about 1/4" of pipe sticking out of the top of the clamp.

In the pic, I have a LITTLE too much protruding, and this DIDN'T make a good flare, and I had to trim it and repeat; but I was struggling to get enough protrusion that it showed up on the photographs.......

With the pipe clamped, you need to fit the flaring die of the correct size into the end of the pipe; they should be marked, but again, use the largest die that will fit inside the bore of your pipe.

The 'button' die is actually the more important of the two dies; it has a pip that seats in the bore of the pipe and makes sire that the press doesn't crush the pipe in on itself or kink, and the end carefully forms the flare on the end between the button and the clamp.

Step 5 - Pressing it home

Shouldn't really have to show two pictures loading the dies in the press, but it is one of those things that often catches people out; designs vary, and you really should check the instructions with your kit, but because I have seen people get all tied in knots trying to get the press over the clamp screws......... MOST kits are designed so that once you have loaded the pipe in the clamp, you put the press over the clamp at 90 degrees, then twist it upright and slide it along and into position over the button die.

But, once you have the clamp on, and lined up over the button die, you can start flaring the end.

It's one of those jobs 80% of it is in the preparation, and this bit is just a question of tightening the screw until the button die touches the clamp!

You are forming copper though, and that is a material that while fairly soft, work hardens.

Thing is not to try and do it all the way in one go, or too quickly.

You have to give the pressure you are exerting with the screw time to form the copper, and you will feel it 'relax' as it flows into shape if you have a delicate enough touch.

Quarter turn, at a time, nice and gently, and within three full turns the flare should be formed.

Watch as the button die descends though to make sure it goes down fairly square and you don't get a lot more metal one side of the flare than the other; making sure your clamp is true and central before you begin helps here, because if that is off it can distort the swage you are making.

When the button die is hard against the clamp die, you SHOULD have a flare formed neatly in the gap in between, but you wont know for sure, until you open it up.

Step 6- Opening the Dies

Picture's a little fuzzy, I'm afraid, but this was a 'good one', and the flare is nice and even and fully fills the recess in the clamp die with a nice neat central hole in the middle. I suppose I should have made some 'bad ones' to show what's not so helpful, but I'm afraid that's one for an 'update' I think!

When the clamp die is removed, though you should have something that looks like a flared end, that you can slide the union op to and get to seal in a brake calliper or joint.

BUT, and I don't think it is too obvious in the picture, but the clamp die will have left ridges in the copper where it gripped the metal during flaring.

These ridges can make it a bit tight to get the union nipple over the pipe and seating nicely against the flare, so the end of the pipe needs dressing first.

Also, the ends have a habit of seizing or corroding on the pipe that can make them a bit awkward when you come to take them off in later years, so before looking at the other end or fitting to the car, we need to do a bit of dressing off.

Step 7 - Dressing off

So the first thing is to dress off the ridges and make the pipe smooth again. Here I have used a flat file just to nib back the ridges, then a quick rub with emery cloth just to smooth it over, but be CAREFUL you don't want any swarf left to get inside the pipe and flushed into the brake workings.

Then to stop moisture or rust and prevent the union seizing on the pipe, sparingly add a little copper slip along the length behind the flare.

This will also help lubricate it so that the nipple will turn more easily on the pipe when you come to fit the pipe up.

Remember, though to put a little copper slip on the other end, having slid the nipple up to the flare, so that the copper slip isn't all pushed up against the flare and the nipple can corrode up at the top end.

Lastly, carefully wipe away ALL excess copper slip, being careful not to get any on the mating face of the flare or in the end of the pipe to contaminate the brake fluid when you have put everything back together again.

But, that is basically the operation of 'flaring'. One end successfully made, and you are away!

Well, not quite, pipes usually have two ends, and you'll probably have to do the same again at the other end, and more than likely, it will need a little bit of shaping once made to make it fit on the car.

BUT; the main bit is done, and you should now be able to make up your own brake pipes, or with slightly larger pipe work, hoses for power steering and stuff like that.

Don't worry, I'm not going to leave you in the lurch at this point; But; if you are tackling the job for the first time, before finishing the job and making a complete pipe; worth while having some practice tries at making one end, and getting it 'just so'.

Cost you about 1/2" of pipe a try, so off the end of your reel, at 60p a foot, you'll only waste about a quids worth in maybe twenty tries!

Part 3 - Finishing a pipe and Warping into place

OK, well, having gone through the process one time round, in words and pics, lets have a look at it in practice, in a vid! Picking up where we left of, having made the first end of the pipe, we check the length we need the pipe to be against the old pipe, or with a piece of wire to make a template; add a little bit for wider bends and a bit more for the flare itself; then repeat the process to finish the pipe, with a swage at either end.

Got that? Want to watch it again? Had a laugh at my freaky hair? Ok, lets fit the thing up and bend it to shape.

Now we haven't looked at that in pics and words, so for those of you without flash players, or sound cards, or cant get you-tube links past the works fire-wall software! Lets have a look at the fitment in stills and text!

Step 1 - Measure up the Pipe

If you are lucky enough to have got the old pipe off in one piece, relatively simple to measure the length from end to end.....

BUT, remember, you will need to have a bit of allowance for making the bends, as well as the flare at the other end.

I err on the side of caution and tend to give a generous allowance, rolling the old pipe along the new, then adding a good thumbs length for bends and flaring........ obviously it depends on how many bends there are, what length the pipe is and how 'tightly' it has to be routed.

To get the length more critically correct, or if you don't have the old pipe in one piece; the best way to work it out is to use a bit of stiff wire, like an old coat hanger, and make a template.

If its simple enough you can put made end into union and flake the reel out to where the other end needs to be, but you'll often find that you don't have access to do that very often.

However, how you establish the length of pipe you need ultimately is up to you; you just need to work it out and allow for bends and ends.

ONLY thing I SHOULD warn, if you are using old pipes as templates, just check against each pipe you are copying, don't PRESUME that the one you got off the nearside brake drum is the same length as the one that came off in three pieces from the off-side! That Murphy will be sure to get-cha!

Step 2 - Cut the Pipe to Length

Using that red pipe cutting tool, if you haven't already, cut the pipe to the length you have measured. The cutter is a delicate tool to use, but cuts nice and cleanly without crushing the pipe or making any swarf..... IF you use it correctly.

Trick is to load the pipe into the jaws of the cutter, and only lightly nip the blade against the pipe. Then wind the cutter around the pipe, nipping the clamp up just a light touch each turn until the pipe cuts. If you wind the cutter blade in too hard, then it will crush the pipe, and that's not helpful.

Step 3 - Flare the Second End

Pretty much as Part 2, steps 1 to 7 all over again;

From pipe and fittings, to completed union termination. Or at least in this case. This is a male or 'single flare union; some pipes need female or double flared unions on them, and I'll show one of those afterwards.

For now, we have a bit of pipe, roughly the right length, with a pair of union on it, and nice neat flares at the ends holding them on.

Step 4 - Roughing them to shape

In the video, I went straight from a bit of straigh-tish pipe to the car, and 'warped' it into place around whatever was there. The principle I used was to start at one end, and work the pipe round what it needed to clear to where it needed to end up.

This is fine, but inevitably, it's not that easy, and you don't have room to bend the pipe as you'd like, because things get in the way.

As shown in the video, I actually lined it up and made the first bend off the car, then attached the end I wanted to work from loosely, before roughing the rest of the pipe into shape; attaching the second end, again loosely, then tightening up the routing from there.

For this pair of pipes, I roughed them out before hand following the pattern of the old pipes.

No real benefit either way; only it was dark, when I made these pipes up so I was working in my kitchen, and I couldn't get the Rangie through the back door to offer the newly made up pipes up!


Take Note:- Always make sure that you have the fitting up against the flare before you make the firs bend!

You'll notice this pipe needs a very tight U-bend close to the end, but it doesn't matter, the unions DON'T like sliding round corners, so if you don't get it on the first section before you begin, you'll have to straighten it all out again afterwards to get it there.... (Remember that Murphey's Law,!) Also, be warned, Copper work hardens, bend it, straighten it, bend it again, straighten it after THAT and the third time you come to bend it, it will snap!

Here I have roughed out the first pipe against the original, and have made the second bend on the second pipe.

If you look closely, you'll notice that I have made the tight U-bends at the end a little longer than on the originals, and the bends aren't any where near as neat, or accurate.

The original pipes are steel, which is why they rusted; and at the factory, they are formed in jigs. The steel pipe can take much tighter corners without kinking, and obviously factory jigs make it a lot easier and more accurate.

Don't worry if you cant replicate the factory pipes shape, it is nearly impossible, and this is JUST roughing out.

Having got the pipes approximately pointing in the right directions, we'll tighten the routing up on the car.

Step 5 - Fitting up the first pipe

Back to the outline at the beginning, having made up and roughed out the pipe, it needs fitting up and fettling into shape. Which end you choose to start at, though, really depends on circumstance.

In this case, the calliper union end is where the tightest clearances are, so that is where I started, as there is least room for manoeuvre.

On the Rangie, there are two pipes, and it is important that you DON'T get them crossed up; as then the calliper pistons will be being pushed by the wrong master cylinder of controlled by the wrong valve in the ABS control block. (Jaqui is an ABS model, and you can just see the sensor wire in the corner of the 'photo')

If needs be, when you take the old pipes off, mark the ports and pipes that each end came off with masking tape of something, to ensure you connect the right holes back together!

So, starting on the lower pipe, as it is obscured by the top pipe when fitted, I warped the pipe into place, lined up the calliper end, and screwed  the union into the port.

However, I did NOT clamp the union up tight, I screwed it in just far enough that the pipe was against the seat in the port, BUT I left it loose enough that it would twist in the union.

This provides some movement to allow me to flex the pipe into shape without stressing it by twisting, or crushing that nice flare I have so lovingly made, until I need it to seal.

Pretty much the same at the other end, where the pipe joins the flex hose.

This is where having room to work is helpful, and choosing the end to start from important.

The pipe has to be pushed into the union all the way, and straight, and it's pretty stiff. not having such close or tight bends near to the union gives you a bit of 'play' to get it lined up and in straight

And again, once the pipe is in place, the union screwed lightly into the coupling, but not so much as to stop the pipe twisting in it.

You can see in the picture the guide on the top of the swivel that is to stop the pipes getting fouled on the suspension. The routing here isn't very tidy, but I have made sure that the pipe is inside and as low as I can get it behind that guide.

But I'm not TOO worried about exact routing at this stage, because I want to get the second pipe fitted up the same way, then I can tidy up the routing of both pipes together.

Step 6 - Fitting Up Second Pipe and tightening up the routing

The same with the second pipe, again working from the tight end first, leaving the pipe loose enough to rotate, but nipped against it's seat in the calliper, then at the flex hose end.

Once the two pipes are in place, and loosely fitted, the actual routing of the hoses can be manipulated and tightened up to suit.

In this instance, the pipes are around the steering swivel, so there is plenty of bits that they could get trapped by, snag on or get caught on, especially if they work loose.

So the routing needs to be pulled in tight away from anything that might harm them, and any excess length, remember I cut the pipes a bit long, JUST in case I had to trim the end down or needed it to make a detour or bend.

Where there is extra length, it needs to be wasted where it wont be in any danger.

Those slightly longer U-bends at the calliper end, were a bit close to the steering arm, so I tightened them up a little and pushed the excess up over the top of the calliper to where it was less exposed.

Conveniently, once past the top of the swivel housing and that guide in front of the suspension spring, there is a much larger 'loop' around and back to the flex hose unions, so that little extra length could easily be spent making those loops just a little larger with no ill effects.

If you have significantly over compensated, and you cant loose that little extra pipe, then you can always trim the flare off the more accessible end, and remake it; BUT, if you made the pipe too short to begin with, then you will have to make another one, and that will tend to waste a lot more pipe than the little you have to account for in routing or trim off.

This is also the other reason for not fully tightening the unions straight away, as if the flare hasn't been crushed into a seal, then it can safely be removed to allow some re-jigging.

But all being well, you wont have to do that, and it's just a case of tweaking the pipes into comfortable routing....

Then JUST to be sure, swinging the steering from lock to lock to make sure that they are clear of everything and aren't going to come to any harm.

That precaution taken, the unions on the ends of the pipes can finally be nipped up to get a good seal.

As you tighten them though, just be careful that the pipe doesn't get dragged round with the union as it's compressed and spoil your alignment; may take a steadying hand on the pipe, and or a final tweak once they are all done up.

Job, done!

Well, almost. Having changed the pipes, there's still the small matter of filling them with new brake fluid and bleeding the system through, but THAT I think is the subject of another article!

Watch this space..... I have just come to do that and found my E-Z Bleed one man bleeding kit missing! So I have to hunt down and severely maim who-ever hasn't brought it back! Typical, bane of having all those 'specialist' tools your advised not to buy until you have a need for them or exhausted chance to 'borrow'!

Part 4 - the 'Double' Flare

Almost a post-script; because I didn't actually have to make a double flare for the Job on Jaqui; but you'll probably find the same, MOST of the flares you'll need or want to make will be male, 'single' Flares; BUT, for completeness, thought I'd better do a double flare to show you how its done, and how they work.

Step 1 - 5 (as Part 2) Make a Single Flare

Exactly as Part 2, steps 1 to 5 all over again; EXCEPT, instead of using a male union fitting, you need to make sure you fit a female one before making the flare. And we DON'T! take the pipe out of the clamp after making the first flare.

1) Take pipe & if necessary, trim end square. 2) Straighten end of pipe in clamp; 3) Put female  union on pipe; 4) Set the Dies; 5) Press the Single Flare......6 - Make the 'Double - Flare'

So, having got to the stage where we have formed the first flare in the clamp, remove the button die, but don't remove the pipe from the clamp.

In fact, you don't actually have to take the press off, just unscrew it enough to remove the button die.

Because to make the 'double-flare' basically, you colapse the single flare back in on itself.

When you formed the first flare, you bowed the walls of the pipe out, right?

Well where they bowed is a gap; so what we are dong is folding the end of the pipe back in on itself, to fill that gap, and give us a concave end form, rather than a convex one.

And we do that by screwing the pointed end of the press  into the end of single flared end, without the button die.

And, the obvious question; why cant you just flare the end like that without using the button die first? Well...... you COULD, but you wouldn't get a very good 'form' on the end, and it wouldn't make a nice seat for the pipe that will fit in it.

Step 7 - Open Clamp & Dress Off

Just as steps 6 & 7 for the single flare; remove the pipe from the clamp, and dress off so that it will seat nicely in the union.

Pictures are a bit fuzzy, I'm afraid, but, in the first, we have single flared joint; left, double flared, middle, and plain pipe right.

In the second picture we have the single & double flared ends joined together.

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