• over_clox@lemmy.world
    link
    fedilink
    arrow-up
    19
    ·
    27 days ago

    It depends which bicycle pedal you’re screwing in. They have opposite threads, designed where they’re self tightening on each side.

    • Mr_Blott@feddit.uk
      link
      fedilink
      arrow-up
      6
      ·
      27 days ago

      Same with gas regulators that attach to the cylinders, for some reason. Oo and some hub nuts on cars

      • SomeoneSomewhere@lemmy.nz
        link
        fedilink
        arrow-up
        6
        ·
        27 days ago

        I’ve heard flammable gas uses reverse (left hand) thread to prevent cross connection. At least for welding gases in NZ; not sure about natural gas.

        • DempstersBox@lemmy.world
          link
          fedilink
          arrow-up
          1
          ·
          27 days ago

          Acetylene does, gas lines are standard pipe.

          Suppose it’s cause natural gas runs at like, 1-3 psi, while a fresh tank of acetylene is 5,000?

          Least in the US

          • SomeoneSomewhere@lemmy.nz
            link
            fedilink
            English
            arrow-up
            1
            ·
            27 days ago

            It’s also torches and everything after the regulator, which run at much lower pressure. At least in NZ

            I think it might be because they’re connected and disconnected regularly so misconnection is a common problem, even with colour coding. Gas work on houses involves actually putting the fittings on pipe and is done by people who should be concentrating more on that rather than on what they’re about to weld/cut.

    • poweruser@lemmy.sdf.org
      link
      fedilink
      English
      arrow-up
      3
      ·
      27 days ago

      If I remember correctly, old timey glass kerosene lanterns also have backwards threads for some reason

      • Akrenion@slrpnk.net
        link
        fedilink
        arrow-up
        6
        ·
        27 days ago

        Gas threads and water threads are opposites to each other for safety reasons. Might be part of that thought.

    • InFerNo@lemmy.ml
      link
      fedilink
      arrow-up
      2
      ·
      26 days ago

      Please tell Tongshen, who manufactures the popular TSDZ2 motor. The pedal keeps coming loose because they don’t do this. I keep a key on me to tighten it when it starts to loosen.