Introduction: A Better Laptop Power Cord

Picture of A Better Laptop Power Cord

Tired of using your laptop in lecture halls with 300+ seats and one outlet... or when all the seats next to the outlets are full? (and you're too lazy to charge your laptop beforehand) You can easily lengthen your power cord to reach 25 feet and add a 3-way plug, while still being able to store it relatively easily.

Step 1: So Here's Your Laptop Cord...

Picture of So Here's Your Laptop Cord...

A big mess of tangled wires with practically no way to organize things... It's like the laptop companies wanted you to hate them. The thick 120v cord is the same length as the skinny charging cord... why? Maybe for when the outlet is 5 feet off the ground? couldn't it just hang off the plug (probably violates some code or law... oh well )

I'm doing 3 things, you can choose to do as many you want and you will still have a much awesomer power cord.

1) Shortening the big 120v cord so it wraps around the brick only once.
2) Adding a 3-way plug to the power cord so I can charge when all the outlets are full.
3) lengthening the small charging cord to 20' to reach farther.

Step 2: Make Sure Your Laptop Cord Is Only 2 Strand

Picture of Make Sure Your Laptop Cord Is Only 2 Strand

I used auto-strippers to look inside the round charging cord that comes from the brick, and confirmed that is only 2 wires (one central wire and braiding on the outside). I think I've seem some laptop plugs with a muli-pronged plug that carry a couple voltages to the laptop, this couldn't be replaced with 2-strand wire.

Step 3: What You Need

Picture of What You Need

mouse over the picture.

Step 4: Cut and Strip the Charging Wire

Picture of Cut and Strip the Charging Wire

No turning back now... Notice that one wire is a coated central wire and the other is braiding around that wire.

Make sure to keep track of your wire polarities at all times!

Step 5: Strip Your Lamp Cord and Add Heat-shrink.

Picture of Strip Your Lamp Cord and Add Heat-shrink.

Lamp cord and most power cords have a rough wire and a smooth wire to distinguish between (+) and (-). If unsure, use a multimeter to check for resistance.

Step 6: Solder Together (don't Forget the Heatshrink!)

Picture of Solder Together (don't Forget the Heatshrink!)

I soldered the wires in-line, just slightly twisted together. Notice one wire is slightly longer to match up with the other.

Step 7: Put the Heat-shrink On

Picture of Put the Heat-shrink On

Use smaller heatshrink for the individual connections, and a big piece to cover those two.

Step 8: Repeat on the Other Side

Picture of Repeat on the Other Side


Step 9: TEST!

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Plug everything in and if your laptop starts charging you're not a failure. You now have a great long laptop cord. If you are a failure, unplug everything immediately, and figure out where you went wrong. Test again after you've spliced the 120v power cord.

Step 10: Time to Shorten the Power Cord

Picture of Time to Shorten the Power Cord

I want my power cord to wrap around the power brick exactly once, so that I'm not wrapping 2 big wires around the brick.

Step 11: Solder and Heat-shrink!

Picture of Solder and Heat-shrink!

Solder just like before but use LOTS of large heat-shrink. Mine is 3 layers thick over the sealed wires.

Step 12: Plug It Back In

Picture of Plug It Back In

I also used some self-fusing rubber tape to tie the 3-way plug to my power cord so it won't come off, or so people won't steal it.

Step 13: Tape the Power Wire So It's Easier to Wrap

Picture of Tape the Power Wire So It's Easier to Wrap

Instead of pointing down, I used the rubber tape to make the power wire point sideways out of the brick instead of down out the bottom.

Step 14: Wrap Things Up

Picture of Wrap Things Up

1) wrap the short 20 foot charge cord around the brick about 3/4 wrapped up.
2) wrap the 120v power cord around the brink the long way, over the and the charge cord. It's only long enough to reach back to the other side.
3) wrap the rest of the charge cord over the big power cord to keep in in place. Put the end through one of the loops or something to stop it from untangling.

You now have a much neater, much longer, and much better power cord.

Please rate this instructable and ask any questions you have.


imark77 (author)2015-06-26

my primary computer is an Apple MPB ( and in case you read my other comment you'll know what my secondary is ). I don't "hard" wrapp and stretch on my cables, as most people know Apple uses cheap inappropriate........................ wire for their cords that breaks easily. I prefer the simple loop method, perhaps with some over under wrapping and a Velcro or twist tie.

they also come with two-pronged ( US ) adapter ends with folding prongs. I think these are great, but i never use them as i am always in situations where the extra 6' is usually needed. so I use the 6' 3 prong extender cord, and in case you ever find an outlet near me; I do carry a 3 prong splitter, and it has 4x spaces at that.

what was the topic again, oh.

I also wanted to put a warning out to anybody who adds the splitter. use a 3 prong 3-way splitter in case you ever find yourself at an outlet with 2 other three-pronged power cords.

imark77 (author)imark772015-06-26

and for yet another comment. I forgot to mention that the two-pronged ( US ) adapter ends with folding prongs have a tendency of wearing out and then arcing. I've played swap-ies twice for somebody else's, and then put on short pigtails.

I also have an iBook G3 with a nice 10 foot DC cord! and no it isn't dead from electrical spikes or noise.

karossii (author)2009-05-03

not that I would truly expect anyone to change such bad habits, especially since it is such a common practice, but wrapping the cord around the power brick is a horrible way to store the power cords. You kink and stress the cables, causing all kinds of potential hot spots, shorts, or just poorly insulated areas which can lead to dirty power. This is only exacerbated by the way you splice lamp cord onto a coaxial cord as stated in another comment. That is one more reason I love my toshiba laptops; they come with an attached velcro cord wrap as a factory standard, and explain how to coil and secure the cable properly. After years working with electronics big and small (but mostly from stage electronics), I know better than to wind up cords like you are showing. You should always loosely coil a cable, alternating which way you're twisting/looping with each turn of the wire. Then secure with cable ties, velcro straps, or even twine or gaffer's tape (though these last two are very poor solutions for your power cord). That will prolong the life of the cables, make it super easy to store them and ready them for use, cause them to lay flat and not tangle with others, etc., etc.

theRIAA (author)karossii2009-05-03

humm.... well I assume the connectors will break down before the wire do... and if the wire do short out, i can just replace then. Over/under coiling is great for 200ft+ sections of expensive AV cable... but I just don't really care when I'm packing up my things after every class. I don't think this lamp cord is going to break. And as for the uneven power, my multimeter shows a constant 19.58v, sometimes spiking up to 19.59 when i throw the cables around like a fool... so about a 0.01v spike max? I'll take my chances... I don't think you start seeing any problems with less then 0.20v consistent changes in voltage. Does anyone have any stories of data corruption with very small spikes in voltage?

imark77 (author)theRIAA2015-06-26

considering this was 6 years ago now, if you still have that laptop I think you're fine.

I just wanted to comment that most of the wrapping issues are with the cheap coaxial cables they use, that degrades and breaks every time it's bent. the lamp cord on the other hand has been around a while. and people do some crazy things with their lamps and you don't hear too many issues of people getting killed by worn-out lamp cords because it's built to much higher standards and safety concerns. I personally like the double insulated European-style, but that's just my preference as it stays cleaner because there are less crevices for dirt.

ChinaMike (author)2009-06-12

Phil B said: "...the lamp cord you used is not much different in size from the 120 volt cord you shortened. I, personally, would have lengthened the 120 volt cord and left the co-axial cord intact. " I believe his reasonins was, not to have that cumbersome BRICK so near the laptop, but to leave it on the ground and away from usable desk space. I for one get so frustrated moving that mess out of the way! I came across this article looking for some advice/help on repairing a damaged laptop charger line. It seems this is not-too-uncommon as I have found myriads of examples, demos, and so on. I do like this (I think!). The extra length could really be useful. I live in Hawaii, and work two part time jobs. One is early morning, the other is later evening, so I have all this day time to kill. The library (state library down town) is magnificent! There is an inner two story courtyard that includes a palm tree or three, but the problem is as he had stated "not enough outlets". I may follow suit with this plan while repairing my damaged cord and add the length! Cheers! China Mike

imark77 (author)ChinaMike2015-06-26

which brand of computer do you have Apple, HP or Del.

then again they all use cheap wire on the DC side because there is less regulations. imagine if they use that type of wire on the AC side, I can only imagine How many people would be dead. case in point Apple had power cords setting houses on fire, because the DC side shorted out by the laptop.

whitefox42 (author)2011-08-04

this is great. I have one problem. I need to splice the end of one adapter plug to another. they both use to work on the laptop but one is a dell brand and one is made in china. I have the one with the wire wrapped around the outside of another wire but that one also has a wire wrapped around another wire. so I have 3 on one cord and the made in china one has two wires and this tiny blue string that has on tiny strand in it. I that what they consider a wire? no wonder the things don't work. I don't have a meter. which ones should I connect?

imark77 (author)whitefox422015-06-26

unfortunately even if you do find a substitute power supply. Dell and HP both use 3 wire cords with a sense circuit in the computer and power adapter "that prevent charging with non-branded adapters!"

however if you just want to extend your current cable, you just need to splice the 3 conductors.

imark77 made it! (author)2015-06-26

I get tired of having a snake with a rat in its stomach, and extension cords only go so far on the AC side. in other words you have a snake with 2 rats.
Now don't get me wrong I do like power bricks, especially the double ended style. I just wish they made one side longer than the other. ( and not by the means of a 3' cord. ) I would love to see manufacturers using a 8' for the device side and 4-6' for the wall.

I have been through many iterations of this so far and have finally worked it down to the current. I started with a connection that fit my universal power adapter and grafted on something ( with a right angle connector!!! ) off of a old cordless phone charger that fit the laptop.

The next-generation involved a little modularity. i wanted to have a bit of breakaway action near the laptop, so I reattached the pigtail to the extension with some ⅛" audio connectors ( BAD IDEA, they weren't rated for the current and had a tendency of shorting on disconnect and melted a little ).

Version 3, by this time I had some ideas of what I would really like.
seeing how the repurposed connection from the cordless phone charger was not rated for the current as well and started to make less and less connection to the laptop ( made painfully obvious by the fact that the battery is dead in my laptop). the same thing happened with the end of the universal charger, as it was made to be universal and was well worn out by the time I got it.
it also had to be modular, so I could use it with other things.
that left me with a bunch of ideas rolling around in my head for a while.
then one day it occurred to me, why not use the correct fitting for my laptop. you know the kind that comes with the laptop, it would even have the 90° end. well I wasn't going to buy a new power adapter when I just bought a new universal, but HAY eBay has pigtails for various laptops! the last step was how to make this both universal and purpose built, it already had an "M" connection at one end so I decided to put one at the opposite end and to make adapters to go to the ACER connectors.

Now I have a tight-fitting 6' extension or a really long 36+'. this allows me to leave all the weight over by the outlet and still wander around with my tablet. ( oh did i not mention that this is an Acer TravelMate C110 ).
now I just need to find a way to stop people from unplugging it on me, or get a new battery?

Generation 3.5. so you might be saying once you have the perfect set up, what can be added?
while I was saying that to, then one day I had to install some emergency / exit lights. and one of the requirements was that there be illumination on the outside of the exit door, well to do this requires 3' of wire to go through the wall to a DC Lamp mounted outside. and what's the cheapest piece of wire at Lowe's? well it's that stupid 6' 2 prong extension cord. I had 3 lights to put in and I picked up 2 just to have enough wire.
this left me with a crazy idea to make a 10" extension cord out of the remainders.

LindaE1 (author)2015-03-23

$10 at a hardware store... problem solved!

JewelA1 (author)2015-01-21

Excellent instructable!

lazydiyer (author)2012-05-04

Simply awesome. Theres some good points in the comments, but honestly, this is such a smart, practical and plain USEFUL idea, that I've got nothing but praise.

Well done !

Prfesser (author)2009-05-03

Very nice idea! Wish I'd had something like this at some of the airports I've visited.

Many power cords to the brick are 3-wire, but the plug-in to the brick is usually a standard connector, and replacement plugs are readily available, so you don't have to tear up the original cord.

Laptops draw low current; my brick says 1.7 amps. Wire can probably be as small as 22 or even 24 gauge but *must* be stranded for flexibility, else it will eventually break.

Great job!

theRIAA (author)Prfesser2009-05-03

Thank you, I went for the smaller cheaper "lamp wire" at the hardware store because i figured that. But I also wanted a cord that was durable, so i wouldn't recommend some skinny crap wire because people are gonna be stepping all over it and it's going to have to hold some weight when you pull things around on accident or coil it up.

jk55092 (author)2009-05-03

Seems like a good idea. When I was in a 300+ lecture hall with a very few outlets, I bought an 8 outlet power strip with 50ft cord. My neighbors loved me.

theRIAA (author)jk550922009-05-03

you carried around a 50ft extension cord? did everyone use laptops in that class?

NikonDork (author)2009-05-02

Simple, brilliant, and rewired/insulated properly. Well done RIAA!

theRIAA (author)NikonDork2009-05-03


ReCreate (author)2009-05-02

This is a bit ingenious...But it could get quite annoying after a while.

theRIAA (author)ReCreate2009-05-02

why is it annoying? I found it faster to wrap and unwrap because i don't have to unwrap the entire thing to plug it in or use it...

ReCreate (author)theRIAA2009-05-03

Yes but such a long cable,not good

Phil B (author)2009-05-03

You have done some good and clever thinking for this project, and it should work out well for you. There are two things I see. One, the skinny charging cord from the brick to the laptop is co-axial. The conductor that surrounds the center conductor is meant to shield and blunt any AC hum and static that might be generated in the power supply so there is a smoother current to the computer less likely to interfere with data transfer within the computer. The same is true of the cylindrical lump in the skinny cord. It is a Balun transformer designed to blunt further any electrical pulses. By introducing a long section of parallel conductor lamp cord you have reduced the amount of pulses causing potential interference that can be attenuated by the co-axial cable. And, the lamp cord you used is not much different in size from the 120 volt cord you shortened. I, personally, would have lengthened the 120 volt cord and left the co-axial cord intact.

knife141 (author)2009-05-03

Excellent instructable! Great idea and nicely done.

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