Coiling a USB Power Cord

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Introduction: Coiling a USB Power Cord

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This is an easy way to tidy up cord that are too long or in the way. Great for the car or desk.

Step 1: Materials

USB cord for your device (Got mine at Dollar Tree)
Pencil
Blow-dryer
Tape

Step 2: Wrapping the Cord

Starting at one end of the pencil, tape down one end, leaving about 5 inches of slack. Wrap the cord around the pencil, leave another 5 inches of slack and tape down. Your wrapped part should be tight and not too pulled. 

Step 3: Setting the Cord

Using the blow dryer on high, blow hot air on it until the plastic is warm. Do this all over the pencil. You can hold the pencil on one end and do this or roll it across a table and blow dry all parts of the coil. 

Step 4: Let Cool and Enjoy!

Let the cord cool until it is cold to the touch. Remove tape, you should be able to pull the pencil out and use your cord!

8 People Made This Project!

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user

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278 Comments

Nice one, it's an old idea, but no doubt many of the youngsters may not of heard of it. A very useful technique in and around the workshop, where stuff gets tangled.
Steve (ex Plastics Engineer)

Thank You, I see the possibility's are endless, "Jumper Cables" maybe.?

Do you mean the kind you use to start one car with another? Because that wouldn't be a good idea...

It would be ok as long as you made sure they were stretched out before you used them but with the crazy amount of current they can carry you could quite easily melt the cables if they were used whilst still coiled. I wouldn't take the risk in case somebody used them wrong.

Yea I was just wondering it this idea would work with an extension cord for my power tools. That's a lot more than a USB cable but a very small fraction of what the jumper cable need to carry (up to 1,000 amps). Power tools 15amp max.

It is inadvisable to coil power cords in this manner.The reason being that thay carry AC current and not DC.

With AC circuits any coil acts as in inductor thus increasing the impedance of the coil so tnat the I(2) R losses become greater thus producing heat.

Sorry mate, but your information is just plain wrong. If you follow this link you'll see how power cable manufactures do it. With long metal poles and industrial ovens heated to 230F (110C). It's the same process as coiling a USB cable, only on a more industrial scale.

Hey man! Thanks so much! I really needed a coiled cable for my project, but I couldent get one I needed, and hair dryer methode isnt really very good. I wanted to use oven, but didnt know what kind of temperature I needed. So thanks one more time. Now I have a coiled cable thats just like from a factory ! Chears

Yes, but....

Inductive reactance, impedance, is a function of both the inductance of the inductor and the frequency of the "signal".

Here,

- Your mains AC is 60/50Hz - so very low,

- And the coiled USB cable, or as many loops as you could possibly put in your extension cord will be such a tiny inductance,

That the reactive impedance (I in your equation) is wayyyy smaller, magnitudes smaller, than the resistance of the copper wire.

Take apart a speaker or a "wall wort" style power transformer to see how many coils of wire it takes (hundreds and hundreds...) to create a significant (in this case both reactive and desired electromagnetic effect) inductor at low (AC mains, or similar bass audio) frequencies.

I was under the impression that USB cables carried DC, not AC

user

BOTH.

The battery charging current thru a USB cord is DC. Loading files thru a USB cord, that is AC.