Background: I have 2 HP laptops at home and unfortunately, both of the the power plugs that go to the power jack of the notebooks have been loose for a while. My sister who is tired of trying to turn the power plug such that it the AC adapter is able to charge the battery keeps on asking me to buy a new AC adapter. But being a student and being tight on money, I figured I should just hack the old adapter and replace the power plug somehow.

This is my solution to my power plug problem. I think took me less than an hour to fix the plugs, and I blame it on my $10.00 solder iron. Hope you'll enjoy my first and hopefully not last instructable.

Step 1: Things You Need...

So let's get started with the list of materials and tools.

Materials:
1. Generic AC adapter package with different attachments
- $9.99 ( I bought another for $6.99)
- if the store charge you more than $10.00 I think you are just in the wrong store. I got the $6.99
one from Tiger Direct (on College Street and Spadina Avenue, Toronto) close to my school
- and I got the $9.99 one from one store along Yonge Street, sorry I can't remember the name
- IT IS IMPORTANT THAT YOU CHECK THE SIZE OF THE ATTACHMENTS THAT COME WITH
THE PACKAGE IF ONE OF THE PLUGS FIT YOUR LAPTOP

2. some zip ties

3. empty sharpie barrel/ empty highlighter barrel
- if the marker is still working, please don't waste it. just improvise of how you can substitute
this part genius!

4. electrical tape

5. you laptop's AC
Tools:
1. solder iron
2. solder
3. pliers
4. wire stripper
5. multimeter
6. hole maker - choose: drill / nail & hammer combo / screw & screwdriver combo / laser ( as long as it can make a hold for the barrel )

Short list eh? Told you this is going to be easy.

Step 2: The Barrel With Two Holes...

You might ask why the barrel is necessary. Well it isn't really necessary, but I just think that it adds protection to your soldered wires as you will see on the next steps. Moreover, I think they look more aesthetically pleasing than having a bumpy wire with bunch of electrical tapes wrapped around.

Steps to prepare the barrel
1. Remove the tip of the marker as well as the ink holder part of it.
2. Bore a hole on the other tip of the barrel and we are done with the marker barrel for now.

Step 3: Cut the Cord

So now we move on prepping the cords.

Generic AC Adapter
1. Cut the cord to desired length. Make sure to leave enough cord length so you could actually solder it to the original laptop cord. As for me, I left a little bit wire on the plug (one that goes to the outlet) side because I might need the adapter and reuse it in the future.
2. Insert the cord in the barrel.
3. Strip the wires, exposing the wires.

Laptop AC Adapter
1. I cut the loose plug that needs replacing.
2 Insert the cord in the tip part of the marker.
3. Strip the wires, exposing the wires.

Step 4: Link Them...

So now we have come to the point of soldering the two cords.

As for me I did a little bit of checking in this step. Using a multimeter, I made sure that I am connecting the wires correctly. So here is how I did it.

1. Check your AC adapter and it should show a diagram there what the polarity is. I've included a picture below showing my AC adapter's polarity. As illustrated in the picture, the outer conductor of the plug must be negative and the core of the plug must be positive for my case.
2. With CARE, plug in your laptop's AC adapter making sure that the exposed wires are not touching. Check which wire is positive and which is negative and take note of them.
3. Now, take your generic plug and check which wire is connected to the outer conductor of plug and which is connected to inner. Make sure you take note of this.
4. Look at your notes and match which wires connect to what.
5. Start soldering the inner part of the wire.
6. Cover the first soldered connection with electrical tape.
7. Solder the last pair of wires.
8. Protect them by wrapping electrical tape on it.

You might say that step 2 is unnecessary because outer part of coaxial is the ground or negative, and the inner wire is positive. Problem is, I don't want to risk my laptop if it turns out it wasn't put that way. I would definitely hate myself if mistake happens since instead of saving money for new adapter, I burnt my laptop which is way more than the adapter. So I guess if you are feeling lazy and will take the risk, then ignore step 2.

Now we move on to finishing.

Step 5: Sealing the Barrel

First of all before I sealed the barrel, I just added a little protection to the connections. I added zip ties on both ends of the soldered section. Reason is, in case someone pulled the cord strongly, then the zip ties will prevent the wires from disconnecting.

So with zip ties in place. I sealed the barrel. And now viola! Just by following the steps you got yourself fixed AC power plug.

Hope you enjoyed this instructable. Cheers!