I have not done this for decades and not on a P38, but what do i need to be able to do some brake lines? a flaring tool (which flare type do we need to use?), some cunifer (size?) some ends (thread/size?) a pipe bending spring one of those proper pipe bender things maybe ? All links/ recommendations welcome... thanks in advance

Rob

A flare tool that can do a double flare, something like this https://www.amazon.co.uk/Silverline-633545-Pipe-Flaring-9-Piece/dp/B000LFXPQ0/ref=sr_1_26 or https://www.amazon.co.uk/Double-Flaring-BOROCO-Degree-Automotive/dp/B0B56PCDXG/ref=sr_1_47, some standard brake pipe size 4.75mm or 3/16" Kunifer copper/nickel or copper pipe and some M10 fittings. If using Kunifer or copper, there's no need for a bending spring or pipe bender as it is soft enough to bend by hand.

The 2nd link that Richard put up is the one to get, it does a great job and is small enough to use in situ, its one of my favourite tools.
I don't know if all model years have them but my 2001 has two complicated looking curly pipes either side of the fuel tank which I made perfect replicas of using that tool and forming the tight bends round a suitable socket using my hands.

The other advantage with the second type is that they will do steel pipes far easier than the first type. I've got one of the first type, in fact I've got 3 for some reason, and when I wanted to replace just one end of a pipe on my son-in-law's Toyota, it really struggled to put a flare on a steel pipe. The pipe was plastic coated along its length except right at the end where it had rusted and ran the full length of the car so just cutting it and putting an inline join in was far easier than trying to feed a pipe along the full length, much like the ones that run over the fuel tank on a P38.

Double Flares ? I had some problems with the second (hand-held flaring tool) type with steel pipe but some grease on the tool threads - on the Op1/2 parts - helped considerably ! As usual lots of inferior offerings on e-bay with these tools unfortunately..

For steel pipes (off the car) I would recommend finding the local 'Pirtek' (if you have one nearby); Hydraulic specialists.

Alternatively there are 3/16" compression fittings- particularly if like me you prefer to use hybrid steel-kunifer arrangements - ie. steel for the straight/er (and more exposed) pipe runs and kunifer for the bendier parts.

Tnx for the advice I hit amazon straight after Richards first post and already ordered the kit from the first link. My first 3 practice flares were a mess, but now looking good....Time to do it for real next. Tnx for your help

The second tool in Gilberts post is now on the wish list.

I have something similar to the other one (but with 1/2" hex instead of the handle so it is ok on steel pipes). But not always the easiest one when working under the car.

4.75 mm (instead of just 3/16) has always sounded a bit like selling 40.64 x 20.32 cm wheels...

th.

It's a bit weird, brake pipes are always 4.75mm or 3/16th inch no matter what the car is even though the ferrules can be either Imperial (on older UK or US built cars) or metric M10x1mm (rather than the 1.5mm thread pitch for a standard M10 thread).

Yes, that finer pitch thread on the nuts/ferrules - ie. Imm rather than the 'standard' 1.5mm - has puzzled me for years too...
and so far no-one I have spken to (in the business) can explain it either.....
It's up there with the other key question as to why they use material for those nuts that is quite soft - so it is really too easy
to 'round them off' - even if/when using proper 'flared' brake spanners !

That does remind me of a useful tip though that works -when they are definitely 'rusted' on- which is to use an impact tool (gently !) with a blunt end to shock them - along with penetrating oil of course - to assist disassemby; Well it often works !

That's worth a try. My method when they have been rounded off by someone using an open ended spanner, is to cut the pipe off (as it is going to be replaced anyway) and use an Irwin tapered socket, with lots of Plus Gas too. If that fails, take the calliper off, put the remains of the ferrule in the bench vice and unscrew the calliper from the ferrule rather than the other way round.

I like it Richard - Mohammed/ Mountain stuff ! If I get that far (and that irritated) I would just replace it all... pipe/flex. pipe /caliper/pads and probably take the pipe bracket off, clean it up and paint it too etc ....
whilst muttering to the car about 'not being beaten by a mere nut' ?!?

Something else I do when talking to car components that are just 'not co-operating' is to say "Ok, so we are doing that now are we ?!" That works a treat (Sounds crazy yes.... but I know I am not the only one who does that..) !

If all else fails, blue spanner, they can't fight back when they are liquid......

are you having troubles getting the fitting to undo, if so you can get a freeze in a can that you spay on to the area and it will freeze the area, it helps, i also use vise grips and just move them back and forwards just enough to flex the fitting, it produces heat and also helps to loosen them. run a drill down the hole on the nipple and spray with wd40 or similar and leave overnight.
FYI vinegar works a treat on salted parts, common to use on boat trailers.
PS i also talk to my car, but it's more a threat to it's longevity and involves matches and after using all the liquids and solvents it would only need a spark. just saying..

Re using the M10 x 1 mm (extra fine / special fine) thread rather than the standard M10 x 1.5 mm thread (coarse) or M10 x 1.25 (fine) for pipe fittings.

All about thread depth. The fine thread is shallower so it's safe in the relatively thin walls of pipe.

Clive

Richard: Not sure about the Blue Spanners but the language is sometimes ripe as in: https://youtu.be/T8YFxuKrJBI

Mad-as: Not too sure about the vinegar though, my favourite freeing liquid is is Acetone/ATF, but not on my chips, obviously !....
I think the key action may be at the first sign of (serious) resistance with the brake nuts is to use vice grips (notably the Irwin types
with a curved part on the jaws) before 'rounding it off' with a spanner ? Of course it usually does not happen in that order though....
As for threatening the car, a handy john-cleese-type shrub might suffice before the pyrotechnics arise... but if they actually do arise
an accelerant like this https://www.supercheapauto.com.au/p/nulon-nulon-start-ya-bastard-150g/13169.html might help free it up first ??

On a more serious note even just turning the fitting slightly with a vice grip - maybe half a turn - causes the fitting to leak and brake fluid is a
penetrating oil. Again the key issue then is the patience to leave it a while to leak like that and thus actually penetrate the treads !

Clive603; You may well be right about the finer thread pitch being used as the fitting is a tube :The nearest I have previously heard
as to the likely reason that it is finer than the 'standard' 1.5mm thread is that 'it is more likely to seize so you have to replace it all !!

davew wrote:

On a more serious note even just turning the fitting slightly with a vice grip - maybe half a turn - causes the fitting to leak and brake fluid is a
penetrating oil.

If you can undo it half a turn, its undone so you don't have a problem.....

Richard RE: " If you can undo it half a turn, its undone so you don't have a problem "

Believe me, if it the threads are badly corroded the problem still exists ! If so you could well damage the nut by further removing it of course.
even with a 'proper' (flared) spanner.. unless you are going to discard/replace it obviously then it really does not matter either way.

I managed to use the method I described above - half a turn and let the brake fluid leak a little to lube the threads - on a rear caliper to good effect.
(As you will know these juctions -pipe to flexi pipe - are at a 45 degree angle so normal penetrating oil is less effective.) The Nut/Ferrule then turned and came off much easier so that I was able to re-use it.

Ahh, there's the difference. I NEVER re-use the ferrules. They are so cheap it isn't worth making up new pipes and using old ferrules that are going to be less than perfect. Then a good dollop of grease on them to stop damp from ever being able to get to the threads.