Solder cable - that's how it works

Anyone who wants to repair toys or household appliances, or occasionally tinkering with electronic parts, will often need to solder cables together. How to do it right and what tools and tools you need for it, you will learn in our clear guide.


As an aid you need

  • the right soldering iron
  • the right solder
  • flux
  • a so-called "third hand"

soldering iron

The soldering iron needs a suitable power. Very low power (15W) electronic soldering irons can not be used for larger cable cross-sections because their performance is too weak. It is best to use a soldering station.

Matching solder

Solders for soldering are available in various alloys. You can use any of them. Make sure, however, that the flux (solder grease) that may be used also matches the solder.

Third hand

A so-called "third hand" is a jig that is especially useful in soldering. But sometimes it can be helpful in other small jobs, once you have "one hand too little". A simple third hand you get from around 5 EUR.

Solder cables together - step by step

  • electric wire
  • Soldering tin (preferably lead-tin, SnPb)
  • possibly flux
  • shrinkable tubing
  • soldering iron
  • side cutter
  • Fixing device ("third hand")
  • lighter

1. Heat soldering iron

First of all you have to preheat the soldering iron. If you are using a soldering station, you should set the temperature in the range of 300° C to 400° C.

2. Prepare the cable

In some cases you will need to strip the cable a bit. Use the side cutter for this. Very frayed strands cut off the best. First clamp both wire ends in the third hand. On one side of the cable, slide the heat shrink tubing (in the isolated area, outside the third hand). Make sure that the wire ends do not touch each other when clamping.

3. tinning

To connect the cables better and safer, you should tin them first. If the wire ends are badly corroded, use some flux. Spread it as thin as possible on the wire ends. Then take up very little solder with the hot soldering iron and coat the two stripped ends.

4. Connect

Loosen one side of the cable from the third hand and then put the two cable ends together and heat the tinning one more time. The material becomes liquid and flows together.

5. Isolate

If the solder joint is hard and cool (after a few seconds), push the shrink tubing over the solder joint. Heat it briefly with the lighter and it lays tight and secure around the previously stripped cable ends. The cables are now firmly and securely connected.

Tips & Tricks

When working, open the window and never inhale solder directly, it is poisonous!

Video Board: How to Solder Wires Together (Best tips and tricks)