Skip to content

Where the theory applies
Loop — fixed

Bowline

Interlock · Climbing

Does not pick a knot

This page does not pick a knot for you. DNA, molecules, quantum braids and vortices stay off Decide.

Bowline, finishedBowline, finished

Finished structure

Drawn from a rope model of this knot: which strand passes over which comes from where the rope actually lies.

Failure modes

When this family fails, it fails as these. The recovered end still outranks the name.

Bowline family

Fixed eye whose lock is a collar seated on the standing part.

  • !Open collar — the eye capsizes under cyclic load
  • !Cowboy / wrong-direction loop
  • !Tail too short to backup, or a Yosemite finish on an unfinished bowline
Fails when
  • !Left unloaded and shaken, so it works its way untied
  • !Repeated slack and snatch on an unattended line with no backup
  • !Tail shorter than a hand's width, especially in slick rope
  • !Small loop made in the working end, so the eye slides closed
Geometry
  • Cowboy / wrong-direction loop

    Collar sits on the wrong part and can capsize

    The working end must go up through the small loop, around the standing part, and back down · step 01

  • Open collar

    Eye inverts or walks under cyclic load

    An undressed bowline is not finished · step 04

  • Tail left up or too short

    No lock, or no room to backup

    The tail must return down the nipping loop · step 03

If you saw this
  • Loop capsizes or the collar walks

    Check

    • ?Collar tight against the standing part
    • ?Tail long enough

    Then

    • Dress and backup
    • Use a figure-8 loop if you cannot inspect a bowline
  • Cowboy / wrong-direction loop

    Check

    • ?Collar sits on the wrong part and can capsize
    • ?Inspect step 01

    Then

    • Retie. Do not dress a defective structure and call it seated.
  • Open collar

    Check

    • ?Eye inverts or walks under cyclic load
    • ?Inspect step 04

    Then

    • Retie. Do not dress a defective structure and call it seated.
  • Tail left up or too short

    Check

    • ?No lock, or no room to backup
    • ?Inspect step 03

    Then

    • Retie. Do not dress a defective structure and call it seated.
Same family

Same failure class, different geometry. Open the plates — Diagnose still starts from the symptom.

This failed — start Diagnose

What holds it

  • ·A fixed loop is a standing eye. The collar or figure-eight body must survive a straight pull without becoming a noose.
  • ·Bowline and sheet bend are the same crossing pattern under different load. That identity is seamanship, not a reason for Decide to swap one for the other.

What topology does not predict

  • ·Fixed vs slipped is a load-path question. Invariants do not choose bowline over figure-eight.
  • ·Ring-loading and slack-shaking failure are physical. Topology does not grade them.
  • ·No UIAA or manufacturer number is inferred here.

Not for

  • ·A lure that must swing on a non-slip loop — this standing eye is a different job
  • ·Letting a climbing identity pick your fishing knot
  • ·Life-critical without a backup
  • ·Slick HMPE (use a splice)
Sources