Soldering wires is slightly different to wiring electronic components to circuit boards because there is very little mechanical force after the components are in place but with wires this usually isn’t the case. If there is going to be a lot of excessive force on the wires some other form of strain relief should also be used such as cable clamps because a simple soldered joint won’t take a lot of mechanical force and in time it will get pulled apart.
First the cables need to be stripped back of the insulation. There are some very good tools to do this and they are well worth buying, if you try to make do with other methods as I’ve seen over the years, people using their teeth! Using scissors and various knives, you will damage the cable by cutting through some of the strands of wire or you’ll damage yourself.
Badly stripped with damaged strands
Once the wire have been stripped you need to twist the end of the wire so the individual strands become one.
Correctly stripped wire with no damage to insulation or strands
Once you have the cables prepared you then twist the two wires together to look like the picture below.
Wires twisted together
Then the normal soldering techniques apply. You simply touch the freshly tinned tip of your soldering iron onto the bare wires for a couple of seconds and then apply the solder, at which point it will smoke and flow over the wires almost immediately and you can withdraw the solder and then the iron and you should be left with a bright silver joint like the one below.
The joint should be pretty mechanically solid and very difficult to pull apart you can then put some sleeving over the joint.
It’s probably more common that you’re going to want to soldering wires onto other things rather than to itself, especially when it comes to building projects in the real world. A circuit board will take care of the small components but there will be stuff that can’t be PC mounted. When it comes to electronic project construction there can be a whole host of stuff that needs to be panel mounted.
Sockets and potentiometers that are intended to be panel mounted usually have tags with holes in them the best way to solder wires to these is to strip back a couple of centimetres of insulation and twist it as before, then feed it through the hole and wrap it around the terminal like the picture below.
Picture of a wire wrapped around a terminal
Then it can be soldered in the usual manner, bear in mind if you have a soldering station its better if you turn up the temperature while soldering bigger items. That’s one of the advantages of a soldering station, if you want to know more or are thinking of buying one click here for a guide.
Picture of the completed joint
Sometimes the terminals won’t have holes so you will just have to wrap the twisted bare wire around it and then solder it. In all cases though you should try to minimise any mechanical stress and not just rely on the soldered joint, soldering in electronics is for making electrically sound joints primarily and they won’t stand up to a lot of mechanical stress.