The Stevedore Knot is a bulky stopper knot tied at the bitter end of a line by passing the working end around the standing part twice before threading back through the initial bight. Unlike the simpler Figure-8 stopper, it adds two extra turns to bulk up the finished knot and resist pulling through larger fairleads or block sheaves. Riggers use it to keep a sheet or halyard from running out of its block under load. On a typical 12 mm braided sheet it produces a stopper roughly 3× the rope diameter — enough to jam reliably in a standard 16 mm sheave throat.
Stevedore Knot Interactive Calculator
Vary rope diameter and sheave throat size to compare Stevedore stopper bulk, Figure-8 bulk, tail use, and jam margin.
Equation Used
The calculator estimates whether a Stevedore Knot is bulky enough to stop at a fairlead or sheave throat. A correctly dressed Stevedore is taken as about 3.0 times rope diameter, compared with about 2.2 times for a Figure-8 stopper. Positive jam margin means the estimated knot bulk is larger than the throat.
- Stevedore knot is dressed and tightened correctly.
- Finished bulk is estimated as 3 times rope diameter.
- Figure-8 comparison uses 2.2 times rope diameter.
- Jam margin is Stevedore diameter minus sheave throat diameter.
How the Stevedore Knot Actually Works
The Stevedore Knot is a member of the figure-eight family — ABOK 526 in Clifford Ashley's catalogue — and it earns its keep when a plain Figure-8 stopper is too small to block the throat of a sheave or fairlead. You tie it by forming a bight in the standing part, then taking the working end around the standing part twice (instead of the single wrap a Figure-8 uses) before tucking it back through the original bight. Pull it snug, then load it. The two extra turns force the knot to balloon out into a fat, near-spherical mass that will not draw through a hole sized for the bare rope.
Why build it this way? Running rigging on sailboats and cargo gear runs through blocks with sheave throats sized for the working line plus a small clearance. A Figure-8 stopper on a 10 mm halyard makes a knot about 22 mm across — fine for an 18 mm sheave, marginal for a 24 mm one. The Stevedore bulks up to roughly 30 mm on the same line, which restores reliable jamming. The extra rope consumed is the trade — you burn about 6× rope diameter of tail to tie it, versus 4× for a Figure-8.
Get the dressing wrong and the knot misbehaves. If you leave the turns crossed instead of laid neatly parallel, it sets unevenly and the bulk ends up smaller than intended — you would be amazed how often a sloppy Stevedore pulls right through a fairlead the tier swore it would jam in. Under shock load, an undertightened Stevedore can also work itself snug enough to be hard to untie afterward, especially in stiff polyester double-braid. The fix is to pre-tighten by hand, then load it once at low force to set it before relying on it.
Key Components
- Standing Part: The loaded section of rope leading away from the knot toward the load. The knot must be tied so the standing part exits cleanly along the axis of pull — any kink at the exit reduces breaking strength by 10-15%.
- Working End (Tail): The free end you manipulate to form the knot. You need a tail length of roughly 6× rope diameter to tie the knot cleanly and leave a 25-30 mm tail outside the finished knot. Less than that and the knot can shake loose under cyclic loading.
- Initial Bight: The folded loop in the standing part that the working end ultimately passes through. The bight diameter sets the finished knot's bulk — a tight bight gives a denser, more reliable stopper.
- Double Wrap: Two turns of the working end around the standing part. This is what differentiates the Stevedore from a Figure-8. Each turn adds roughly one rope diameter to the finished knot's overall bulk.
- Tuck: The final pass of the working end back through the original bight. The tuck must exit on the opposite side of the bight from where the wraps started, otherwise the knot dresses as a slipped variant that sheds bulk under load.
Who Uses the Stevedore Knot
The Stevedore Knot lives wherever a running line passes through a hole or block that is bigger than the rope itself, and where losing the line through that hole would create a real problem — a halyard escaping up the mast, a sheet running out of its turning block, a hoist line dropping out of a snatch block on a derrick. It started life on cargo docks (hence the name) where stevedores tied it on the ends of running lines aboard steamships, but the same logic applies anywhere modern fairleads, blocks, or clutches outsize the rope they pass.
- Sailing — Cruising: Stopper knot on the bitter end of a jib sheet running through a Lewmar 30 mm car-mounted fairlead on a Beneteau Oceanis 40, where a Figure-8 has been known to draw through under flogging loads.
- Cargo Handling — Historic: Tail-end stopper on cargo runner lines aboard early 20th-century freighters, used by stevedores on the Liverpool and New York docks loading break-bulk cargo through ship's derricks.
- Sailing — Racing: Stopper on spinnaker halyards aboard J/109 and similar one-design keelboats, where the masthead sheave is sized generously for fast hoists and a plain Figure-8 occasionally pulls through during a botched takedown.
- Theatrical Rigging: End-stop on counterweight arbor purchase lines at venues like the Stratford Festival Theatre, where the line must not escape upward through the head block during a runaway.
- Arboriculture: Stopper on climbing line tails passing through hollow-block friction hitches, preventing the tail end from disappearing into the hitch under a sudden descent load.
- Tall Ship Sail Training: Tail stopper on running rigging aboard sail-training vessels like the Picton Castle, where deck crew handle 18-24 mm manila and polyester lines through wooden blocks with generously-sized sheaves.
The Formula Behind the Stevedore Knot
There is no force equation specific to the knot itself — what a rigger actually needs to predict is the finished knot's bulk diameter compared to the throat of the block or fairlead it must jam in. At the low end, on a 6 mm dinghy line, the finished Stevedore is around 18 mm across and works in any standard small-boat fairlead. At the nominal mid-range — 10 to 12 mm on cruising-yacht running rigging — it produces a 30-36 mm stopper that reliably jams in typical 18-24 mm sheaves. Push to the high end on 18 mm tall-ship manila and the knot grows to about 54 mm, which is bulky enough to handle wooden blocks with 30 mm throats but consumes nearly 110 mm of tail to tie. The sweet spot sits around 3× rope diameter — which is exactly where the Stevedore beats the Figure-8's roughly 2.2× ratio.
Variables
| Symbol | Meaning | Unit (SI) | Unit (Imperial) |
|---|---|---|---|
| Dknot | Finished knot bulk diameter — the smallest hole the knot will not pass through | mm | in |
| drope | Nominal rope diameter | mm | in |
| k | Bulk multiplier — empirically ≈ 3.0 for a well-dressed Stevedore in polyester double-braid, ≈ 2.7 in stiff manila, ≈ 3.2 in soft nylon | dimensionless | dimensionless |
| Ltail | Minimum tail length consumed to tie the knot plus leave a safe tail outside it | mm | in |
Worked Example: Stevedore Knot in a coastal cruiser jib sheet stopper
Your shorthanded sailing club in Port Townsend Washington is re-rigging a fleet of 6 J/24 keelboats for the summer training season, and the head instructor wants every jib sheet finished with a stopper that will not draw through the Harken 27 mm fairlead cars under flogging loads when a sheet is accidentally let fly. The sheets are 10 mm Marlow Doublebraid polyester. You need to confirm the Stevedore is the right choice over a plain Figure-8, calculate the finished bulk, and work out the minimum tail length to leave when cutting and whipping the sheet ends.
Given
- drope = 10 mm
- Throat of fairlead car = 27 mm
- k (polyester double-braid) = 3.0 dimensionless
- Tail length factor = 6 × rope diameter
Solution
Step 1 — at the nominal Stevedore bulk multiplier for polyester double-braid, calculate finished knot diameter:
Step 2 — compare to the 27 mm fairlead throat. The knot is 3 mm larger than the throat, which is the kind of margin you want — comfortable, not borderline. A Figure-8 in the same line would only give about 22 mm, smaller than the 27 mm throat, and would pull straight through.
Step 3 — at the low end, if a crew member ties it loose and leaves the wraps crossed instead of parallel, the bulk drops to roughly k ≈ 2.5 in this rope:
That is the failure mode you train against. At the high end, an over-tightened knot in soft new line can swell to k ≈ 3.2 right after tying, but it settles back to ~3.0 after the first hard load cycle, so design to the nominal figure not the freshly-tied figure.
Step 4 — minimum tail length consumed plus 25 mm safe tail outside:
Result
The finished Stevedore on the 10 mm sheet sits at roughly 30 mm bulk diameter — 3 mm proud of the 27 mm fairlead throat, which is exactly the comfortable jamming margin you want. A loosely-dressed knot drops to about 25 mm and slips straight through, while a freshly tied tight knot can hit 32 mm before settling back to nominal after the first load cycle, so plan around the nominal 30 mm. If you measure a finished knot under 28 mm, the most common causes are: (1) crossed wraps where the two turns lay over each other instead of side-by-side, which collapses the bulk by 4-5 mm, (2) using stiff aged polyester that has lost its plumpness — re-tie with fresh line, or (3) leaving the bight too generous before tucking, which stretches the knot long and thin instead of round and bulky. Cut each sheet end leaving at least 85 mm of tail past the planned knot position before whipping.
Stevedore Knot vs Alternatives
The Stevedore Knot competes directly with two close cousins in the figure-eight family. The decision usually comes down to throat size of the block or fairlead the knot must jam in, and how much tail you can spare. Pick wrong and either the knot pulls through the hole or you waste rope.
| Property | Stevedore Knot | Figure-8 Stopper | Double Overhand Stopper |
|---|---|---|---|
| Finished bulk multiplier (× rope diameter) | ≈ 3.0 | ≈ 2.2 | ≈ 2.5 |
| Tail consumed to tie | ≈ 6× rope diameter | ≈ 4× rope diameter | ≈ 5× rope diameter |
| Ease of untying after heavy load | Moderate — works snug under shock load | Easy | Hard — tends to lock up |
| Reliability in slick line (Dyneema, slick polyester) | Good — extra turns add grip | Marginal — can shake loose | Good |
| Best application fit | Halyards/sheets through oversized blocks | General-purpose stopper on most running rigging | Climbing tails, slick rope ends |
| Tying speed for trained crew | ~8 seconds | ~4 seconds | ~6 seconds |
Frequently Asked Questions About Stevedore Knot
The most likely cause is rope condition rather than tying error. Aged polyester double-braid loses cover plumpness and core fill after a season or two of UV and wash cycles, and the bulk multiplier drops from the nominal 3.0 to as low as 2.6. On a 10 mm line that means the finished knot shrinks from 30 mm to 26 mm — under your fairlead throat.
Squeeze the rope between thumb and finger near the knot. If it flattens easily and stays flat, the cover is tired. Re-end the sheet with fresh line, or step up to a Double Stevedore variant (three wraps instead of two) which restores the bulk. The other check is rope construction — single-braid and parallel-core lines bulk less than double-braid at the same nominal diameter.
The decision is purely geometric. Measure the smallest throat the line passes through — typically a fairlead car, a clutch jaw, or a sheave cheek — and compare to 2.2× and 3.0× the rope diameter. If your throat is between those two numbers, the Figure-8 fails and the Stevedore wins. If the throat is below 2.2× rope diameter, save your rope and use a Figure-8.
On modern cruising yachts with oversized self-tailing winches and generous fairleads, this calculation surprisingly often pushes you toward the Stevedore. On dinghies and small keelboats with snug fittings, the Figure-8 still does the job.
Two extra turns mean two extra contact areas where rope-on-rope friction welds the knot under shock load. This is worse in stiff polyester and worst in wet manila. The cure is mechanical pre-setting: after tying, hand-tighten by pulling the standing part and the tail in opposition, then load the knot once at maybe 20% of working load to bed it. A pre-set knot deforms predictably under later shock load instead of cinching down further.
If a knot does lock up, work the wraps loose one at a time with a fid before pulling the tail — never just yank on the tail, which welds it tighter.
You can, but the bulk multiplier drops to roughly 2.4 because Dyneema has a tighter, slicker construction and the wraps lay flatter. On a 6 mm Dyneema halyard the finished knot is only around 14 mm — barely larger than the rope. For HMPE lines, a stitched stopper ball or a brummel-spliced stopper button is a better engineering answer than any knot.
If you must use a knot, the Stevedore beats the Figure-8 on Dyneema by virtue of the extra turns providing more friction surface, but plan on it occasionally working loose under cyclic flogging.
Leave at least 2.5× rope diameter of tail outside the finished knot — 25 mm on a 10 mm line, 40 mm on a 16 mm line. Anything less and cyclic loading from flogging sheets or slatting halyards will progressively work the wraps tighter, consuming the tail until the knot capsizes into a slipped variant that sheds bulk and pulls through.
This is the single most common cause of a stopper knot failing weeks or months after it was tied perfectly — the tail crept inward and nobody noticed. Whip or heat-seal the tail end so you can spot any creep at a glance.
Yes, slightly. Any knot reduces breaking strength because the rope bends sharply around itself; the Figure-8 cuts strength to roughly 65-70% of straight-line breaking load, while the Stevedore drops it to about 60-65% because the second wrap adds another tight bend. For a stopper knot at the bitter end of a sheet or halyard this almost never matters — the line never sees breaking load there.
Where it does matter is if you ever load the stopper directly, for example by accidentally cleating off the wrong side. Don't design rigging that relies on a stopper for primary load — that is what splices are for.
References & Further Reading
- Wikipedia contributors. Stevedore knot. Wikipedia
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