2810: How to Coil a Cable

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How to Coil a Cable
The ideal mix for maximum competitive cable-coiling energy is one A/V tech, one rock climber, one sailor, and one topologist.
Title text: The ideal mix for maximum competitive cable-coiling energy is one A/V tech, one rock climber, one sailor, and one topologist.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a CLIMBING MARINE A/V TOPOLOGIST - Add links to all relevant coiling techniques - Please change this comment when editing this page. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

When left unattended, long cables often develop knots and look messy, especially if there are several different cables. The causes of this are not well understood, but may relate to socks disappearing in the wash and to clothes ending up within duvet covers. Cables are often carefully coiled - arranged in a compact series of loops - to take up less space or avoid tangling with other cables, either for storage or when only part of a cable's length is needed to make a connection, only to be later found to have tangled and deformed themselves. Cables often remain curved or uneven after uncoiling.

In this comic, Cueball is struggling with such a problematic cable, and blames flaws in the construction of the cable for causing it (step 1). Well-meaning people then descend upon him, eager to share their obscure knowledge of cable-coiling technique that they claim will avoid these issues (a bit like in 208: Regular Expressions). Long, confusing, and potentially contradictory explanations ensue (step 3), and they eventually coil it themselves (step 4). Cueball is unlikely to be able to reproduce this process himself, and may still find deformations in the cable later; he will likely need to return to step 1 the next time he needs the cable coiled.

However, it turns out that all of this was intentional on Cueball's part. It is even presented as a four-step tutorial called "How to coil a cable". Apparently, it is crucial to wrongly (and loudly) blame the cable in step 1. This might elicit a faster response than just asking for help, analogous to Cunningham's Law, which states that "the best way to get the right answer on the Internet is not to ask a question; it's to post the wrong answer". After all, posting the wrong answer will cause some people to compulsively correct it.

The obvious way of coiling a cable - taking hold of the cable's trailing end as it leaves the hand, and bringing it back around into the hand in a circle, so it forms a simple helix - causes the cable to twist along its length in the same direction for each turn, and requires the person unraveling it to cope with the twisting.

The title text mentions several diverse specialties that have something to say about cables, lines, and/or knots.

The audio technician's way of coiling a cable involves alternating each obvious helix loop with a backhand loop (backwards helix turn) where the loop curls the same way as the other loops, but its 'helix height' is backwards so the trailing end ends up between the rest of the gathered cable and the previous loop. This causes the twists and antitwists to cancel out, resulting in a cable that does not twist while coiled and uncoiled.

The rock climber’s way of preventing twists and tangles in a rope involves “Flaking” a rope - running it through your hands and piling it loosely - which is used when unwinding a coil in to a pile on the ground. This also affords the climber to quickly detect damage and kinks by feel. The reference to rock climbing appears later in the title text when having a rock climber present is mentioned.

A figure-8 coil is used on some boats: the rope is held in one hand, and wound across the forearm to loop under the elbow, then back across the forearm and through the hand in the same direction each time. This also avoids twists.

In general, though the stiffness and cross-sectional profile does affect the tendency to tangle, a similar cable built for the same purpose is likely to suffer from almost exactly the same tendency to tangle when handled the same. As such, the blame laid upon the brand of cable is generally a spurious excuse for what is more likely just down to handling issues. Some particularly problematic cables, such as those used to connect headphones/earphones to their coaxial plugs (which are deliberately thin, flexible and may bifurcate into a "three-ended" Y shape with comparatively large terminating housings on all its ends – all potentially confounding factors), can be sometimes advertised as "tangle-free". Usually this seems to be by using a flat-profile cable, for some reason, and yet almost invariably they also do actually succumb to tangling anyway, as they are repeatedly used and then being shoved back in a pocket or bag with a more or less cursory attempt at neatly coiling them to save untangling time later.

In the comic, however, Cueball appears to be coiling up something akin to Christmas lights (or another more technical cable with many mid-cable side-tapped connectors) which, most people would know from experience, definitely adds potential for tangles to form when not carefully enough handled during coiling and uncoiling, as well as if disturbed (e.g. rummaged through, looking for something else in its container) during a period of storage.

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
How to Coil a Cable Properly
[A drawing of a tangled cable appears below the title.]
Step 1
[Cueball is standing holding a tangled mess of cable in both hands. Each end of the cable is dragging on the ground.]
Cueball: I need to buy a different brand of cable! This one always twists into spirals and gets tangled.
Step 2
[Ponytail enters the panel from the left, and White Hat enters from the right, to come to Cueball’s rescue.]
White Hat: No! That's because of how you're coiling it!
Step 3
[White Hat holds and coils the cable while he, Hairy, and Ponytail attempt to explain the method behind the cable coiling. Ponytail, White Hat, and Hairy all have the same speech balloon, with many of the words replaced by scribbles to indicate that they are talking over each other and/or that Cueball can only make out a few phrases. Only the following dialogue in the word balloon is legible.]
Ponytail / White Hat / Hairy: ...over-under method... ...figure-8... ...quarter-turn... ...flaking...
Step 4
[White Hat presents the well-coiled cable. A caption with an arrow points to the cable:]
Neatly coiled!


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Discussion

I don't actually know what name of 'coiling' it has, but the way I was taught to coil an AV cable (by an AV technician), and these days mostly use with long (garden-mower) power extensions, was maybe the 'quarter-turn' - though it's not a quarter, so maybe not - in finger-rotating the latest "end of loop" around the axis of the cable to leave it effectively twistless in its looped form (whilst introducing a 'one twist per loop-so-far' longitudinal twist in the still trailing unlooped cable that easily 'rolls-out' as you progress towards the free end/drag the length towards you). Done right, it's like smoothly 'drum-winding' the cable. But you can over-/under-twist the cable (especially if it has an internal/inherent twisting, like those christmas lights probably have with probably two entwined single-cores) so you may need to keep an eye on the multiloop you're forming and backtrack a bit if it looks like it's starting to figure-of-eight from the combined helical forces. But tricky to get perfect, may have a bit of a loop-twist (that only stays untangled due to it being ultimately hung on a hook). Maybe I've just not been taught the right methods by a powercord expert. 172.70.90.20 19:39, 2 August 2023 (UTC)

That first method is pretty much how I was taught by a guy with rather expensive microphone cables. It really does help the cable to last longer, since it's not stored with a twist. As a bonus, coiling a rope or extension cord this way also lets you throw it without it tangling in midair. Just make sure to hold onto/step on the non-thrown end... 108.162.237.142 20:12, 2 August 2023 (UTC)
I don't think they're meant to be Christmas lights. The lumpy bits that look a bit like lights are, I think, meant to be knots in the cable. 172.70.210.148 15:45, 3 August 2023 (UTC)

Another profession that deals with hose/cable managment is nursing (e.g. in operating room). Don't know if they have any techniques distinct from those in the mentioned professions. 172.69.135.82 21:50, 2 August 2023 (UTC)

Still wondering how topology factors into this... as of this comment, there's no explanation. - 172.70.130.234 22:38, 2 August 2023 (UTC)

Probably referencing Knot Theory. 141.101.76.97 23:17, 2 August 2023 (UTC)
I think the relevant mathematical concepts are curvature and torsion, which belong to differential geometry, not topology. 172.69.59.24 19:28, 8 August 2023 (UTC)

As a sailor once explained to me, the AV method (over/under) can potentially form a clove hitch around one's ankle while on deck, hence their use of figure-8. Meanwhile, there's another technique espoused by the likes of 'Essential Craftsman' where you basically use a chain stitch to hold it all together. Nayhem (talk) 00:35, 3 August 2023 (UTC)

I have a flat extension cord that was stored for some years using the "chain stitch" method. I ended up hanging the center of the cord from my garage ceiling for a week to get the worst of the kinks out, then wound it around a 5-gallon bucket to try to flatten it out some more. For the sake of your cables, DON'T use the chain stitch method!


This sentence makes absolutely no sense to me:

... alternating each obvious helix loop with a backhand loop (backwards helix turn) where the loop curls the same way as the other loops, but its 'helix height' is backwards ...

I think I need an "Explain Explain xkcd"... 😕 IMSoP (talk) 10:03, 3 August 2023 (UTC)

The idea of enlisting the help of an "expert" reminds me of how my father would always have the best charcoal barbecue at the picnic site. He would bring the charcoal and lighter to the picnic area and then walk around to see what everyone else's barbecue looked like. When he identified the best burning site, he would would walk over to the barbecue master and say to that person something like, "Excuse me, I really admire how your fire is burning, my kids are over there and I'm a little embarrassed that I don't really know how to do this. Could you show me how you got such a great fire?" The expert was always willing to build the fire for him. That's how, time after time, we always had a great burning barbecue. -- [[User:{{{1}}}|{{{1}}}]] ([[User talk:{{{1}}}|talk]]) (please sign your comments with ~~~~)

My reading of the comic was different to what's currently in the explanation. I read it as Cueball has just uncoiled the cable ready for use, and is annoyed at all the kinks and tangles that have resulted from it having been coiled up. The others are then so keen to demonstrate how to do it better, that they end up coiling it all back up again, which doesn't actually help him in the slightest. Which seems funnier to me. 172.70.211.190 15:34, 3 August 2023 (UTC)

My reading of the comic is also different... With (or in spite of) all this dubious help, he just bought a shiny new cable in step 4! Mathmannix (talk) 11:22, 4 August 2023 (UTC)

There is some controversy over "flake" vs "fake", see https://tradewindssailing.com/wordpress/?p=1343 for example. I learned "fake," the comic uses "flake." IDK.

Methods explained

The over-over(quarter turn twist)


The over-under https://youtu.be/JtOGJZ_gYy8 https://youtu.be/cpuutP6Df84

Chain technique https://youtu.be/L7av0C0jWQw

See also https://people.maths.bris.ac.uk/~majge/hjce.06.pdf "Knotting probability of a shaken ball-chain" 172.70.251.170 10:08, 3 August 2023 (UTC)

White Hat presents the well-coiled cable

“Neatly coiled!” doesn’t look like a speech bubble, but more like an annotation bubble—it uses an arrow instead of a simple line. Thus it is not a “White Hat presents”, but the final step in this tutorial.--162.158.111.19 08:40, 4 August 2023 (UTC)

White Hat is still presenting it, even if he's not saying anything while doing so. And the transcript doesn't present it as speech by White Hat.172.71.242.191 11:10, 4 August 2023 (UTC)

Missed the joke

I feel like people missed the joke on this, which is the proper way to coil a cable is to say you need to buy a new cable due to kinks, and you will have multiple people tell you how you are coiling your cable wrong, while coiling it for you. Thus cable coiled. 172.71.223.77

As an A/V technician, often in 'amateur'/volunteer environments, this seems to be somewhat of a rite of passage. Commonly, either 1) a new teammember will wrap a cable in such a way I would find improper to leave like that for the next person to find, or 2) a visitor is willing to help teardown. Either case results in 'the conversation' where the technician gives some instruction and guidance. Aronb (talk) 20:26, 9 August 2023 (UTC)