Soldering is a handy skill that has many uses, like splicing wires, soldering circuits, and even making jewelry.
The perk of soldering is that it doesn’t require many tools. Usually, you’ll need two things: a soldering iron and a solder. However, even if you don’t own a soldering iron or gun, you can still use tools you probably own, like a lighter or a steel wire, to substitute for a soldering iron.
So, how to solder without a soldering iron? This article will give you two methods to solder wires and electronic circuits without needing a soldering iron.
1. Solder Using a Flame
Instead of a soldering iron, you can use a lighter, a candle, a blue torch, or any other heat source that can reach the solder’s melting point.
Generally, most used solder alloys have a melting temperature between 360ºF to 400ºF.
Here’s how to solder with a flame:
Take Safety Precautions. Before getting all technical, you must first take some safety precautions:
-Avoid wearing oversized clothes. They’ll get in the way while soldering and risk burning you.
-Always wear safety glasses to protect your eyes from any solder splashes.
-Work in a well-ventilated space away from any flammable items.
-If you’re soldering wires inside a car, make sure to put a non-flammable board underneath the wires to prevent hot solder from dripping onto the car’s carpeting and starting a fire.
-Wash your hands and the working space when you finish soldering.
-Lastly, discard waste solder in lid containers and label the container as hazardous.
-Only do this if you have experience with it. Take the necessary precautions.
Gather the Necessary Equipment
Next, gather the needed equipment. Luckily, soldering requires only a few tools:
-A heat Source
-A wire cutter
-A wire stripper
-Heat shrink tubes
-Rosin paste flux (optional). The rosin paste flux protects the wires from oxidation during heating—the oxide layer makes soldering difficult and can affect the wires’ connection.
Do the Soldering
Now we get to the soldering part. Soldering electric wires is easy. All you need to do is join the wires and use heat to melt the solder to connect them. To do so:
Strip the Wires
Using a wire stripper, remove at least an inch of insulation from the wires’ ends. Be careful not to break any strands from the wires while stripping the insulation to avoid damaging them.
Damaged wires have increased resistance. Increased resistance produces more heat, blowing the fuse. If the fuse doesn’t blow, the wires may melt and cause a fire.
Put the Heat Shrink Tubes
Slip the heat shrink tubes beyond the wires’ ends so they don’t tighten while soldering. Make sure to choose a heat shrink tube that is thin enough to fit tightly over your wires upon heating.
-Splice the Wires
-Twist the wires’ ends separately.
-Overlap the wires to form an X.
Then, spin the wires around each other, but leave a small space between the wires’ insulation and the twisted ends.
Make sure to tuck the wire ends so they don’t stick out and pierce the heat shrink tube.
A bonus tip: before twisting, you can scrape the wires’ edges using sandpaper to improve the wires’ conductivity.
Plumbers often solder copper with a flame.
Solder the Wires
First, put a layer of the rosin flux onto the wires.
Once this is done, apply heat under the wires directly using a lighter.
Gradually feed the solder on top of the wires while heating with the lighter. You don’t need a lot of solder, just enough to cover the wires without forming droplets.
Start from the middle and move outward. Make sure not to add solder to the wires’ tips touching the plastic insulators.
Once you’re done soldering, remove the lighter and let the wires cool.
Cover the Wires’ Joint With Heat Shrink Tubing
Lastly, slip the heat shrink tubing over the soldered area. Heat the shrink tubing using a lighter or a heat gun. Just make sure to start from the middle and move outwards until the tube shrinks.
2. Solder Using a Steel Wire
If you want to solder on a circuit board, you’ll have to use something to act as a soldering iron, like a steel wire or a nail—directly heating the circuit with a flame will damage it.
-Make Your Soldering Iron From a Steel Wire
To make your soldering iron alternative, you’ll need: A piece of metal that could be a wire (preferably 14 gauge or more), metal rods, nails, or screwdrivers.
Make sure to use metals that’ll retain heat, like stainless steel. While copper and aluminum heat faster than steel, they’ll cool off quicker, making it harder to melt solder.
Using a plier, bend the steel wire so it resembles the tip of a soldering gun.
Tin Your Steel Wire Tip
Tinning will make the steel wire tip last longer by preventing rust. It’ll also help speed up the heating process from the tip to the solder. To tin the steel wire tip:
Heat the edge of the steel wire.
Then, add a small amount of solder to cover the tip.
Lastly, wipe the wire off on a damp sponge. That’ll remove excess solder and leave a thin protective layer.
If you’re going to use a nail or screwdriver, you should also tin their tips before soldering.
Heat the tip of the soldering steel wire by holding it over a flame for 20-30 seconds.
Apply heat for around 2 seconds to the joint you want to solder on the circuit. Make sure not to overheat it, as this may damage some circuit components.
Then, touch the solder with the heated wire tip and bring the solder down to the circuit.
Remove the solder and then the heating tip.
Repeat the same process of heating and soldering until you’re done.
Soldering without a soldering iron is actually achievable. You can use a heat source, like a lighter or a candle, and directly heat the wires. If you’re going to solder an electronic circuit, you can use steel wire, nails, or screwdrivers as an alternative to a soldering iron.
No matter what you’re going to solder, you should always remember to take safety precautions so you’re always safe during your DIY soldering project.