I bought 100 feet (30.5 meters) of 1/4 (6.4 mm) rope the other day. When I was coiling it up I was remined of the discussion about the rescue boat remote control wire.
It doesn’t seem intuitive at first why a rope or wire twists when taken off a spool improperly. Difficult to visualize at first. I had to hold the coil in my hands and feel the twist to really get the idea.
Turns out that it is literally convoluted.
Convoluted comes from Latin convolvere , meaning “to roll up, coil, or twist.” It is related to the verb convolute , meaning “to twist or coil.” Once something is twisted it can be literally and figuratively difficult to unravel, and can be convoluted .
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Thank you Kennebec you made my day!!
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When a rope is coiled up, a twist is put in each loop, but the resulting coil has no twists. Seems counter intuitive. The are equivalent apparently, the rotation used to coil wire on a drum and the twist that goes into each loop, just different orientation.
The ideal mix for maximum competitive cable-coiling energy is one A/V tech, one rock climber, one sailor, and one topologist.
Here’s a remark at this site at this site How to Coil a Cable explaining that xkcd cartoon.
“I think the relevant mathematical concepts are curvature and torsion, which belong to differential geometry, not topology.”
I first saw the over-under method of coiling high-pressure paint hose at a northern Asia newbuilding shipyard over two decades ago and subsequently watched so-coiled hose being deployed in preparation for coating application - an operator would take the spray-gun end of the hose and walk it out in a straight line flat on the ground, absent the long length of coils that usually resulted, and then needed tedious straightening out, when the over-over method of coiling had been practiced following the last use of the hose. So simple, yet so effective. Observing an experienced operator use the over-under method at job completion and prior to stowage was just pretty to watch, a hundred or so metres of line gathered together at astonishing speed.
I have routinely used the method since to coil a heavy-duty electrical extension cord after mowing the lawn – no kinks, twists or untoward turns the next time grass calls for a trim
I somehow doubt ease of use where wire rope or mooring line is involved.
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I thought I invented this when I was 18, but I’m sure it wouldn’t bear up to research. I began to do this when packing up the wire shrouds on my 18’ catamaran, because the coil would like to spring open the over/over method. Being very interested in labor saving methods, I soon learned that the over/under works from even the middle of a wire shroud without dis-attaching the fastened ends. When it came to re-stepping the mast on the next sail, it was easy to release the bungee holding the coil to the mast and simply walking the mast aft from the gallows. The wire rarely snagged on things,
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