How-To/DIY: Soldering Copper Wires

Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal (solder) into the joint, the filler metal having a lower melting point than the adjoining metal.

Warning: Use this guide at your own risk. I am not a professional and am not responsible for injury to you, your vehicle, or anyone/thing else if you choose to follow this guide.

You are gonna want to gather the necessary items for this task:

  • solder
  • soldering iron
  • heat-shrink tubing
  • lighter/heat gun
  • wire stripping tool

Zip-ties and the wire stripper tool just makes it easier. My harness was covered in electric tape and male/female connectors which was all removed. I recommend fixing one wire at a time to avoid confusion.

Although I fixed most of the wires already in the following images, I left one unattended to teach the basics of how to solder copper wires. Once you know the steps, it’s basically the same for all the other wires. So let’s begin!

Here you can see my tools and supplies I will be using for the How-To/DIY: Soldering Copper Wires.

Soldering Copper Wires (1)


Step 1.

I remove the female/male connectors and strip the wires about a quarter (.25″) of an inch off. Then cut a proper size heat shrink tube that is about an inch long or whatever length that will cover the exposed copper and some of the wire’s looming for a strong hold. Remember to add the heat shrink tube first.

Soldering Copper Wires (2)

Step 2.

Twist the copper together.

Soldering Copper Wires (3)

Step 3.

When you power the soldering iron, allow it to heat up for about 20-30 seconds which will be very hot to touch so be careful not to burn yourself.

Begin “tinning” or adding a thin layer of solder to the tip. You know you did it correctly when you see smoke rise off the tip and a silver/chrome color. Place the soldering iron’s tip under the twisted copper wires and allow the tip to heat the copper. This part takes awhile, dependent on the thickness of the wire so be patient. Now place solder on top of the twisted copper wires and allow it to soak or melt into the strands. Don’t add too much, just enough to blend the solder and copper together.

Soldering Copper Wires (4)

If done right, it should look something like this:

Soldering Copper Wires (5)

Step 4.

After the iron has cooled down, place the heat shrink tubing you added before over the it. Heat the tubing up so it can shrink over the wires with a back and forth motion if using a lighter. If you have a heat gun, then blow hot air directly onto it and you will see the heat shrink tubing become smaller and wrap the two wires together. Don’t hold it in a position too long to avoid any kind of burning.Soldering Copper Wires (6)Soldering Copper Wires (7)

I finished up by using zip-ties for the whole harness for a strong hold and then used electric tape to wrap it all.
Soldering Copper Wires (8)Soldering Copper Wires (9)

Well that is pretty much it for this article of How-To/DIY: Soldering Copper Wires and hope that you learned something new today. Thanks for reading and have a great day! 😀

Leave a Reply