Brake pipes and Hoses

Discussion in 'Mech Tech' started by Tilly, Jun 18, 2018.

  1. I ordered a hard copper brake pipe kit for Tilly and when I came to use it I noted the end fittings were different.
    see picture
    Obviously the original on the left has the conical mating sealing formed fitting and the new has the inverted flare, I do not think that the new type replaces the old type as it will not seal correctly in the brake pipe.
    right or wrong
  2. Yes they are incompatible
    The bus needs DIN flare and that new fitting is SAE flare
    Moons and snotty like this.
  3. Correct. Copper is also an inappropriate material for brake pipes. Your options are as follows:
    "Bundy tube"- double walled copper brazed steel tube to SAE J527
    Cunifer to DIN 17664
  4. davidoft

    davidoft Sponsor

    Nothing wrong with copper it was used for years just cupro nickel is better, steel is fine too
    snotty likes this.
  5. Copper is much easier to work with. It is just more susceptible to work hardening and vibration damage. Having said this, this is over very long periods of time. copper is better than steel as it is easy to work and rust free. As said above though the SAE fittings are no good. You will need to send it back to get DIN fittings. Or, cut them off and replace them with DIN fittings. Any good motorfactors shop should be able to do this. if they take off the very minimum, you should still have enough pipe. The fittings are cheap enough.
    snotty likes this.
  6. I spoke again today with the supplier who had spoken to the manufacturer.
    All manufactured pipes in stock and those sold have this double flared fitting and the manufacturer says if you tighten them up they should not leak and it will be ok.
    I asked for a return and they are going back today.
    I thank the supplier for the for the help given but after this I think I will find a new source for brake pipes and fittings.
  7. davidoft

    davidoft Sponsor

    the original flare is a single flare the new one is a double flare, I think DIN flares have a flat rear whereas sae flares have a conical rear, the nut and fitting to which it is going to be fitted is what designates the type of flare, as the new flared pipes are copper its possible to tighten the fitting enough to distort it to fit and seal but its not correct and wouldn't work with steel
  8. Correct Davidoft. The DIN flares have a rounded outer but the rear of the flare is flat to fit snug against the DIN union fitting. You can easily make your own if you can borrow a pipe bending tool and a DIN flaring tool. It works out so much cheaper too.
    Tilly, snotty and davidoft like this.
  9. just purchased the flare tool Cupro nickle pipe, male unions to suit and cutter total price £80 will have some fun cutting bending and fitting over the next few days.
    Valveandy and paradox like this.
  10. How much pipe did you order? one 25ft roll should be enough.
  11. It's good fun. Very theraputic...
    Tilly and earlylatebay like this.
  12. Copper may have been used on vehicles but:

    -It was never used on the VW bay. So these buses haven't been homologated or tested with copper brake pipes.

    -It has not been used at the very least since 1981, which is when the first edition of DIN 74234 was released. DIN 74234 does not allow copper brake pipes, just cunifer, double walled steel, and single walled steel cold drawn (Rare and a bit pants).

    If a copper brake pipe snaps due to the work hardening that it's susceptible to, and you fitted it, your insurance will definitely be invalid. Cunifer is just as nice to work with- why take the risk?

    Also, if the supplier is telling you to use the SAE flares anyway, they're giving you very dangerous advice. Do not take it.
    77 Westy and Tilly like this.
  13. This is bad advice. The joints won’t seal properly.

    The flare tools you bought are pretty good - I got the same. Not super professional quality, but will make a tidy flare with a bit of practice.
    Tilly likes this.
  14. That’s absolute rubbish
    Best fit some asbestos brake shoes as well then.
    snotty and davidoft like this.
  15. One roll 25 feet all from Motor parts direct
    earlylatebay likes this.
  16. I tried it out on one of the caliper pipes and it does a good job.
    i agree with all that has been said about using the flared and tighten up, I feel it is very bad advice and it is obvious that the made brake pipes are wrong and should be fitted with a Din end on them , I just wounder how many have been sold and put to use, if you look at most popular suppliers on line they all offer them for sale.
    maybe one or two would like to add their voice to the discussion
    snotty likes this.
  17. I've found that the best pipe bending tool around are your thumbs.
    And no I'm not taking the p*ss, this is actually a sensible reply from me to a thread for a change!
  18. As @Suss said, for copper or cunifer, your thumbs are all you need. You're (hopefully) not going to be making very sharp bends, and a bender wouldn't help there anyway. For steel pipe, you would need a bender.
    Mark Darby likes this.

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