Useful Knots for Portable Ham Radio

By Scott Schillereff, VA7SNJ, March 2025

 
Good knots are indispensable for successful set ups in portable ham radio (and life in general!).  I describe here six highly useful knots, along with seven additional knots (honourable mention) which are also handy.  All of these knots are easy to tie, stable when properly loaded, and allow you to make fixed loops, join ropes, make adjustable and fixed tie-offs, and bind things together.

Each knot is described below.  For my six preferred knots, links are provided to online videos on how to tie them.  There are many additional videos online for tying just about any knot.  Table 1 (below) presents a summary of reference information and recommended applications for all 13 knots.  A knot-tying guide (Figure 7) provides a crib sheet for tying the six preferred knots.  (Note: this guide is not intended for life safety applications).

Knots are a personal thing and there are numerous alternatives to those presented here.  Feel free to try these and others to find your favourites.

Knot Efficiency and Dressing

Any knot introducing a sharp bend to a rope weakens that rope (typically to ~40-80% of original rope strength) due to uneven stress distribution within the knot.  Knot efficiency (%) is the strength of the knotted rope divided by the strength of the unknotted rope (x 100).  Other factors being equal, it is best to choose knots with highest knot efficiency.  The six knots highlighted in Table 1 have relatively high knot efficiencies.

For best performance and efficiency, a knot should be well dressed, that is, after loosely tying, it should be incrementally snugged and shaped to have the best form and symmetry before it is loaded.  Simple knots (like those here) can be dressed using fingertips or a pointed tool (e.g., mechanical pencil, small Phillips head screwdriver filed into a marlinspike, or a nail). With knots, as with many worthwhile things in life, you should “dress for success” 😊.

Interestingly, when a rope is passed around a round object with diameter four times or greater than that of the rope, rope strength is not reduced (called the 4-to-1 Rule).  This means, for example, that a guy line cord wrapped around a thick tent stake would be stronger than the same cord wrapped around a thinner stake.

Finally, the ease of untying is important in choosing a knot.  Some knots are inherently easy to untie (e.g., Zeppelin Bend).  Some knots can be tied as a “slip” version, where the last pass of the end of the rope (working end) is a small loop (bight).  By pulling that bight out, the knot collapses and the rope can be easily recovered.  In contrast, some knots are notoriously difficult to untie after heavy loading (e.g., Double Fisherman’s Bend, which is not on my preferred list for that reason).  At the extreme end of things, the Constrictor Knot is nearly impossible to untie after heavy loading and must be cut off.

My Preferred Knots

Bowline

  • For me, the King of Knots. Easy to tie (even with one hand), stable, secure; has many variations and applications
  • Useful to make fixed loops at the end of a rope (e.g., to attach a support line to an insulator for wire antennas)
  • Moderately easy to untie
  • Battle-tested; in the movie Hacksaw Ridge, the hero Desmond Doss used a Bowline-on-a-Bight to create a seat sling to lower wounded solders to safety during the Battle of Okinawa in WWII.
  • Link: https://www.animatedknots.com/?s=bowline

Taut-Line Hitch

  • My go-to knot for an adjustable friction hitch (e.g., for guy lines, or adjustable tie-offs)
  • Easy to tie (can also be tied in a quick-release slip version)
  • For slippery rope, add an extra half hitch for added grip when you finish the knot
  • To save time, friction hitches can be left tied in each guy line and simply readjusted at each set up
  • Link: https://www.netknots.com/rope_knots/tautline-hitch

Siberian Hitch (also called Evenk or Evenki Hitch)

  • Forms a stable, fixed tie-off, and unties quickly, simply by pulling the tail
  • Can be tied and untied with gloves on so well-suited for cold weather or hazardous conditions when you’d rather not remove your gloves
  • Link: https://www.animatedknots.com/siberian-hitch-knot

Trucker’s Hitch

  • For me, the Prince of Knots – an adjustable tension hitch with mechanical advantage
  • This hitch forms a two-pulley system, creating (ideally) a 3-to-1 mechanical advantage on the main rope (standing part). In practice, friction between the moving ropes and the anchor point reduces this ideal ratio somewhat, but it’s still powerful.
  • Easily tied and adjusted (e.g., after a load has settled or if the rope needs tightening)
  • Many /P radio applications (e.g., securing guy lines, antenna wires, tent or tarp ridge lines, adjustable tie-offs, securing gear on roof racks, and more).
  • Since two slip knots are used within this hitch, the entire knot can be easily and quickly undone by simply pulling on the tail.
  • Link: https://youtu.be/zvUB6AGWHQ0

Zeppelin Bend (also called Rosendahl Bend)

  • A lesser-known, but very stable, secure bend (knot for joining two ropes)
  • Best for ropes of equal or nearly equal size
  • Originally used to tether zeppelins and blimps in the early 20th (You will want to learn this knot if only for historical homage to zeppelins and the Zepp antenna!)
  • The hallmark of this knot is how easy it is to untie, even after heavy loading; just pull out on the two loops on the outside of the knot and it just comes apart– magic!
  • Link: https://www.youtube.com/watch?v=xX9Hdpru0dw

Constrictor Knot

  • A powerful binding knot; essentially an overhand knot with a retaining strand (riding turn) over the top
  • Like a boa constrictor, it can keep tightening, but doesn’t easily release
  • Very useful knot for binding things or as a fixed anchor point on a pole or pipe
  • Can also be used as an emergency substitute for a gear clamp (radiator hose clamp), cable tie, or circular clamp
  • WARNING: it is nearly impossible to untie this knot even after moderate loading! Try tying it (gently) on your finger to see.  After heavy loading, this knot is rock solid and must be cut off. Treat rope used in a Constrictor Knot as sacrificial.  (For a recoverable binding knot, consider the Clove Hitch or Arbor Knot (see Honorable Mention Knots), or many alternative binding knots (search online)).
  • Link: https://www.animatedknots.com/constrictor-knot-rope-end-method

Honorable Mention Knots

Alpine Butterfly

  • Elegant, secure, stable knot to make fixed loop (static anchor point) in middle of rope
  • Can be loaded in any direction
  • Does not require access to either end of rope
  • Moderately easy to untie.

Double Fisherman’s Bend

  • Classic, secure, stable knot to join two ropes of equal or near-equal diameter
  • Low profile, so passes over obstacles (e.g., tree branches) quite well (especially if taped to form a tapered lump; good to form a longer throw-line from two shorter ones)
  • Difficult to untie after heavy loading (but could just cut off, if using cheap cordage).

Clove Hitch

  • Classic hitch to join a rope to a pole, branch, or another larger rope, with intended loading at right angles to the pole (can come apart if loaded parallel to the pole)
  • Useful as starting knot for lashing (see Round Lash below)
  • Not reliable alone as a terminal anchor knot (can shake loose when weakly loaded).

Tensionless Hitch

  • Hardly a knot at all – simply 4-5 turns around a larger-diameter anchor (e.g., tree trunk) finished with a couple of half hitches onto the in-coming rope (standing part)
  • Friction of the wraps against the anchor secures the knot under load; if the anchor surface is smooth (e.g., metal pipe rail), more turns may be needed
  • Knot is 100% efficient when the anchor diameter is ≥4 times the rope diameter
  • Good knot to anchor an antenna support line when lots of cordage available.

Timber Hitch

  • Simple knot originally used to haul logs
  • When snugged and loaded, the multiple twists seize against the log (or pole) and friction prevents the knot from slipping
  • Can be loaded in any direction; if loaded parallel to the pole, best to add a half hitch farther up pole in direction of pull to keep knot aligned
  • Very easy to untie
  • Can also be used as a starting knot of various types of lashing.

Arbor Knot

  • Easy to tie, forming a very secure, stable fixed anchor knot
  • Especially useful when there is little rope available for a knot
  • After loosely tying, the Arbor Knot can be gently snugged and forms a kind of secure noose (e.g., to lower tree limbs after cutting)
  • Alternatively, the Arbor Knot can be “ratcheted down” by swinging the standing part (rope leading away from the knot) back and forth while pulling on it. Friction between the two component overhand knots as they tighten seizes the standing part, effectively locking the knot with each “ratchet”.  With ratcheting, this knot can become very tight.
  • With gentle to moderate loading, the Arbor Knot is easy to untie; however, after “ratcheting”, it can be very difficult to untie and need to be cut off.
  • Can also be used as a start knot for various types of lashing.

Round Lash

  • A simple lashing knot for binding two poles together (e.g., an antenna pole and a fence post).
  • Can use variety of fixed anchor starter knots (Clove Hitch, Timber Hitch, Arbor Hitch) on one pole, then 6+ turns tightly wound around both poles, then finished with a Clove Hitch on the other pole.
  • During wrapping, can temporarily loop the rope in hand around a toggle (e.g., short stick, screwdriver, tent stake) to make a handle for stronger pulling. Pinch the turn to maintain tension, then repeat on the next turn.
  • If tying a round pole to an angular anchor (e.g., to an angular fence post or rectangular picnic table leg), start with a fixed anchor knot on the rectangular object and finish with Clove Hitch on the round pole.

Summary of Knots and Applications

Notes

1 Knot Efficiency = strength of knotted rope/ strength of unknotted rope (x100).

2 Reference no. in Ashley Book of Knots (1944, and recent revisions; ISBN 9780571096596)

3 E = easy (fingers); M = moderate (fingers, tool); D = difficult (tool), I = impossible (cut off).

4 100% efficient when anchor (e.g., pipe, post, tree trunk) ≥4 X rope diameter.

5 Efficiency depends on efficiency of weakest component, typically the starting or finishing knot.  For the wrap section with poles ≥4 X rope diameter, efficiency is 100%.

6 Ease of untying depends on loading.  Light loading – E; heavy “ratchet” loading – D to I

Knot Tying Guide

This figure presents a guide for tying the six preferred knots.  Each knot should be dressed to final compact form before loading.  Use this handy guide to practice tying these knots over and over until your muscle memory is such that they tie themselves (e.g., when watching TV or in your spare time while waiting for FT8 DXCC…😉).