Caution: The Clove Hitch (ABOK # 1245, p 224) was, originally, included here with the intention of condemning it. It does have two giant faults: it slips and, paradoxically, can also bind. It should be deeply distrusted when used by itself.
Uses: However, the Clove Hitch can be very useful:
Theater Scenery: Thanks to Curtis Mortimore of Ball State University for providing this example; when adjusting stage curtains hanging from a bar, a clove hitch round the bar allows the height of the bar to be adjusted up or down by rolling the knot slightly. At the right height, a couple of Half Hitches round the standing end provide security. Some months after writing this I heard independently from David Winch of the Sydney Opera House who said they were desperately trying to stop staff using Clove Hitches and use the Round Turn and Two half Hitches instead. Their two comments amplify the introduction - it can bind and it can slip!
Boat Fenders: Similarly, when attaching a boat's fender to a railing, the fender's line can be initially secured with a clove hitch and then, when adjusted, secured with two Half Hitches round the standing end.
Dangers: As stated above, the Clove Hitch's problems are slipping and binding:
Slipping: I watched a friend trying to dock his 53' Hatteras. Each time the bow mooring line was handed to the marina assistant, he used a clove hitch to attach the line to the dock's post. The offshore wind was blowing the stern away so my friend used his engines to swing the stern in. Each time he did so the strain was too much for the Clove Hitch, which slipped undone. This process was repeated seven times despite increasingly forceful requests that some other knot be employed to secure the line. Reviewing the events later it became apparent that the assistant was using the only knot he knew. It is not a knot to be used alone.
Binding: Finally, if you make the knot secure by stacking on additional Half Hitches, i.e., multiple clove hitches, then you are inviting a major strain to cause the earlier turns to bind tightly and become impossible to untie. So, if on a boat you feel an urge to use a clove hitch - resist! Choose something else unless you are merely hanging a fender
Alternatives: There are good alternatives available:
Paradox: When you tie this round turn and two Half Hitches, in the process you actually create a clove hitch round the standing end!
Disclaimer: Any activity that involves ropes is potentially hazardous. Lives may be at risk - possibly your own. Considerable attention and effort have been made to ensure that these descriptions are accurate. However, many critical factors cannot be controlled, including: the choice of materials; the age, size, and condition of ropes; and the accuracy with which these descriptions have been followed. No responsibility is accepted for incidents arising from the use of this material.