Today’s column discusses why things like ropes and strings tend to get tangled in knots.
Some observations from handling extension cords - the process of coiling a rope, cord, etc induces twists along the length of the cord. There is a technique to alternate over/under coils to prevent cummulative twisting, but that increases the possibilities for the cord to tangle.
Take a rope, coil it, then stack the coiled rope. Now try to extract the end and uncoil the rope by pulling the end. Unless the coils are neatly laid one over the other in such a way to remain in that order, the coils will shift and move during the coiling process, creating overlap of the successive coils. This process can be sufficient to provide the coils enough disorder to lead to tangles.
Size of the coil compared to diameter and stiffness of the cord can also be an issue. Large loose loops with a thin, soft rope will tend to allow twists and overlaps to snare.
Securing the ends does help. It prevents an end from crossing through a coil during the handling process, when those coils are shifting around each other.
There were actually several people who had asked similar questions to the one that launched this week’s column. Many of them were about phone cords. Many of you probably don’t know what those are, they have to do with obsolete technology of landlines. Anyhow, even though they’re “linked” when hung on the phone receiver, they get tangled more’n anything. More even than my granddaughter’s hair. Partly because when you talk on the phone, you add twists – changing hands, moving about, etc. Partly because they’re already coils that get intermeshed.
Yes, phone cords are the worst, because of the twisting that occurs during handling. People move in patterns, so if you establish a pattern of hand changes that rotate more one way than the other, the cord twists build up. I’ve undone more than my fair share of twisted phone cords because I couldn’t stand it.
If you consciously pay attention to how you handle the phone, you can undo any twists you make as you put the phone back. Basically, if CW twist answering, then CCW putting down. For some reason, it isn’t that simple in practice. You swap hands, then swap back a couple times, and you don’t reverse the twist, you continue the twist.
This. Several points here. The string lies relatively motionless once at rest, so the knots must be formed while the string is moving. It moves most when it is being stored and again when it is being taken out. Your knots must form either when storing the string or when you retrieve it. The string also moves because of the twisting introduced when coiling it. Time lapse photography should show that the ends move around as coiled rope attempts to untwist itself.
My observations are that knots start when you drop loose ends into the middle of coils or loops and then are completed when you pick the string up. Shaking the storage box around will move the ends around even more, making multiple knots.
Loops in and of themselves are not the answer, although most cord and rope management devices such as spools are basically means of looping the string and holding the ends in place.
I have seen two extremely effective means of preventing knots without twisting the string.
The first is that used by old Hollywood gaffers who work a lot with electrical cords. It is also used a lot by Boy Scouts. This is the crochet method, or controlled knotting. You tie the string into a long series of slip knots looped through each other, as if you were crocheting. You can then just throw the cord or rope into a pile and it will not knot. This shortens the string, controls the ends, prevents damaging twisting, and stiffens the cord or rope. This is how I store the cords for my lighting systems. I just plug the cord into an outlet and as I walk to the lights or whatever the slip knots pull out, giving me just the length I need.
The second method is the throw bag method used by small boaters in rough water. It is popular with lifeguards and other people who might have to throw a rope. One end is tied to the bag or other container such as a bottle or hollow ball. The other end sticks out of the top of the container. You just stuff the rope into the container, leaving the free end out. No need to be orderly about it. Just stuff the rope in there. Don’t try to coil it or loop it or do anything to make it look ‘neat.’ The container is small, so the rope can’t move around in there, and the ends are prevented from contact with any loops inside the container. The free end is usually tied into a bowline or similar non-slip loop for ease of hanging onto the rope when the bag is thrown.
The way the line in a throw bag is deployed is to hang onto the free end and throw the bag. Works better if the bag is weighted, but you don’t want to weight it too much if you are using it for rescue. Knocking the victim on the head with a lead weight is bad form. The bag also usually contains a piece of styrofoam or something to make it float. You can throw a well-made bag much farther than you can a coiled rope or life ring.
I use the throw bag method for camp ropes and things like that. You can make your own rope storage bag this way: get a stuff sack that is barely large enough to hold your rope. Cut a small hole in the bottom and run the rope through it. Tie a large knot in the end so it can’t come back through the small hole. Stuff the rope into the bag, being careful not to twist the rope, leaving the free end hanging out. Pull the drawstring of the bag closed.
I have seen jewelers use the throw bag method for necklaces. Get a zip lock bag and punch a tiny whole in the bottom. Feed the necklace into the bag, leaving one small loop sticking out of the tiny hole. Leave another small loop sticking out of the top and zip the bag shut as far as it will go. No tangles. Also prevents scratches.
Basically, you want to prevent free ends from falling through loops. And you want to avoid twisting your lines. That is how the knots get formed. Anything you do to restrict movement of the ends and keeping your lines from twisting will keep knots from forming. Twists are springs. They will move.