This article will show you the proper way on how to solder wires together. The process of soldering is taking two or more wires and joining them together and then using heat to melt electrical solder connecting those two wires permanently. When done properly you have a strong conductive connection that turns two separate wires into one.
And learning how to properly solder is a very useful skill to have.
Whether it’s for wiring an LED light bar like in project nightlight where i welded up a roof rack and then wired some bright LED lights on my truck to illuminate the trail both forwards and in reverse. Or project police interceptor where I wired police lights, a siren, dash camera and other electronics to make a fully functional police car for a police officer.
And looking forward we have the #driftstang which is my drift car project where i’ll be wiring gauges and other goodies into that car, and we’ll also have project night light relay where I’ll be wiring a winch a bunch of off-road lights and also be fabricating a front and rear bumper at a metal for the truck. And these two projects are going to require a good amount of soldering so I figured now is the perfect time to teach you the proper way to solder and the best part is you don’t need many tools.
Here are all the basic tools that you’re gonna need.
You ‘ll need a good soldering gun, flux and solder, a good wire strippers, heat shrink tubing, a heat gun, safety glasses, and a sponge.
Now while these are all the products that you’re going to need, I’ll also show you some other products that you might already own and you could use as well.
And before we begin on how to solder wires here are a few safety tips:
- Always use safety glasses so if the solder pops or splashes it won’t get in your eyes.
- And although it’s common sense soldering irons get hot, so you don’t want to touch them and you don’t want to lay the tip down on anything cause it’ll burn.
- Want to make sure you pay attention to where you’re soldering and don’t solder near flammable materials and also if you are soldering inside a car or something you don’t want the hot solder to drip onto the carpeting and start a fire.
- So always slide something non-flammable underneath that if the solder drips down it’ll drip on this instead.
- Another thing you don’t want to do is breathe in the smoke from soldering.
- So make sure you use a fan or work outdoor sin a well-ventilated area.
- And the final safety concern is most solder has led init and you’re going to be touching the solder so when you finish soldering you want to clean off your workstation and wash your hands, specially before handling any food.
And with those simple safety precautions in mind let’s get soldering and soldering is really easy to do and what makes it easy is using the correct tools.
And one of the most important tools is the solder you use.
There are three main types:
- Leaded solder
- Lead free solder
- Silver solder
You don’t want to use this metal working silver solder which is designed to connect metals together like tubing and sheet metal.
The other thing is this silver solder has an acid corn it so it’s not meant to be used on wires because over time the plastic insulation will get eaten away and expose the wire and cause a short.
Both of these will work to solder wires together, and lead free solder is more environmentally responsible but let free solder just doesn’t work as well Lead solder is easier to work with because it soaks into the wire strands better and has a lower melting point so that’s what I primarily use and I prefer this 6040 rosin core solder which gives me the best results and a quick tip just in case you want to know what kind of solder you have maybe you have unlabeled solder and you don’t know if it’s lead or lead free solder this is how you could tell.
On the left I’m using lead solder and you could see once it finishes cooling down lead solder has a shiny look to it. On the right i’m using lead-free solder and once that finishes cooling down it has an etched or corroded look to it.
It’s not shiny. So that’s a quick tip on how to tell if you’re using lead or lead free solder.
I already mentioned that i like using rosin core solder because the rosen protects the wires from oxidation but i like to go one step further and use arosin paste flux which is another layer of protection from oxidation.
When you heat up metals like the wire end you’re going to solder, or even your soldering iron as the unprotected surface heats up oxide form and coat the copper and make it really difficult to solder.
And it could even create a bad connection.
I use this rosin paste flux which is non-acidic it actually comes from tree sap and you just coat the wire like that and now the wire is protected.
If you don’t use flux trust me try it out it’s inexpensive and it makes soldering easier and your soldering job that much better and finally the last important tool that you’ll need is a soldering iron or soldering gun. Now I like the soldering iron because when you turn it on it stays on versus pulling the trigger on gun.
This is a smaller soldering iron so it’s really good for smaller gauge wires, nothing thick. It has a narrow tip so it’s good for working on circuit boards and in really tight places. But when soldering and cars i prefer using a soldering gun this is a 140 Watt and you could use this on thinner wires or because it’s more powerful you can even use it on thicker wires like this.
And if you use a soldering gun you’ll know that you need these specialized tips for and They are about five bucks each so they could get a little pricey but i have a little trick.
What I like to do is I like to go to my local hardware store and buy this seven strands non insulated electrical wire, this cost me one dollar and from this big wire you could cut smaller strands of wire at about five to six inches long and then what you do is you bend the wire so it’s shaped exactly like your store-bought tip.
And throughout this whole article I’ve been using my homemade tip and they work great.
From one of these strands for a dollar, you can get about 14 tips versus one of these tips that you buy which is five dollars each. So that’s my quick tip on saving a bunch of money on making your own tips.
And if you’re working somewhere remote where you don’t have access to electricity, you can get one of these portable butane torches, and they sell these adapters that go right over the top which could easily melt solder. So now you know what tools to use for soldering, i’m going to show you the five simple steps to solder.
First you need to strip the wires, then add your heat shrink tubing, physically connect the wires,solder the wires together, and then shrink that heat shrink tubing to make a waterproof connection.
The first step is you need to strip your wires.
You could use an automatic wire stripper like this which,is actually pretty nice. You just put the wire in, pop it, and the wire is stripped. These wire strippers are great they’re nice and easy, but personally I like using one of these old-fashioned wire strippers.
So you can see written on the wire strippers, are the different gauges of wire.
I know this is 12 gauge so you just slide that into 12 and you want to have about the same amount of length stripped of each wire which will make connecting them easier. Now just squeeze down on the strippers and twist back and forth a few times. And then while squeezing pull the insulation off, and that’s all there is to it. And one thing to be careful of while stripping wires, is breaking the strands off the wire.
Even though It seems insignificant if you remove only a few strands that could increase the resistance and heat up the wire in that area and if a fuse doesn’t blow, the wire could melt and cause a fire. So if you break any strands by mistake,just cut the wire and redistribute so you don’t have any strands missing. Αlright, with the wire end stripped, we can move on to step two.
For step two you’re gonna grab your heat shrink.
I like having a kit like this. It has bunch of different sizes and colors and when picking your heat shrink you want to try to find the thinnest heat shrink that will fit over your wires.
The really wide heat shrink like this, that has a lot of space around the wire, isn’t going to shrink enough to seal the wire. So that’snot going to work. You want something like this, which just barely fits over the wire and when this gets heated up, it’ll shrink nice and tight. Now make sure you have enough heat shrink to cover part of the insulation and all the exposed wire. And don’t forget to slide your heat shrink down the wire and slide away from the area that you’re gonna be soldering, because the heat generated from soldering could actually shrink the tube.
Now for the third step we’re going to connect these wires
there’s a few different ways you could do it. I have two ways that I use all the time and they pretty much cover every situation.
The first method is get these two ends and unravel all the strands, spread them apart a little bit just like that, and you’re going to want to do that on both sides.
Now you’re going to inter mesh these two strands together like that and then you’re going to twist. So that’s the first method, inter-mesh the strands twist them together, and it looks just like this.
The second place I want to show you is called alignments splice or western union splice. Make sure you have enough wire stripped and twist those strands tight. Then make an X and spin one wire around the other wire and just keep spinning each wire around the other as tight and neat as you can until you run out of wire to twist. You don’t want the copper strands to stick out, so make sure you tuck the ends in so they’re flush with the wire. I hope you are getting a full picture on how to solder wires
Copper strand sticking out could pierce the heat shrink and then cause a short.
Now which splice should you use? Well they both work great so try each one and see what you like.
With the wire splice together, you want to use a helping hands which holds the wire steady for when you solder. Now a quick tip is I cover the end of the alligator clips with heat shrink tubing because the bear alligator clips are sharp and cut through the wire insulation exposing bare wire. Now use the helping hands to hold the wires in place and we’re ready to add our solder. First rub the rosin flux into the wire. Get it all over the wires because this is going to help the solder flow into the wires. Then you’re gonna grab your soldering gun and heat it up by holding the trigger down. As it heats up use a damp sponge to wipe the tip and remove all the oxidation. You see how the tip is tens and I just removed all that oxidation is nice and shiny now that’s what you want to see.
Now in this case my soldering tip is already tined but if your tip is bear you’re going to want to tin it.
So heat the tip up and just add a little bit of solder to cover the tip.
Then wipe off the tip on a damp sponge to remove all but a thin layer of solder, which is going to help the tip last longer and it’s also going to help speed up the heat transfer from the tip to the wires.
Now is the most important step. We need to heat up the copper wire using our soldering gun.
So place the tip of the soldering gun underneath the wire and feed just a little bit of solder in between the tip and the wire. This solder is going to melt against the tip and wire so it’s going to speed up the heat transfer between the tip and the wire. Thicker wires do take a little bit longer to heat up but after a few seconds you should be ready to add solder. You want to add the solder at the top of the wire. You don’t want to touch the solder to the tip.
You feed the solder into the copper strands and let the solder wick through the strands. You don’t need a lot of solder either, just enough so that the strands are coated. You don’t want blobs of solder. Once you added enough solder remove the soldering gun and let the joint cool. Don’t touch the joint until it’s completely cool because if you touch the joint it will move the wires around while the solder is still in a liquid form and that could create cracks in the solder or air gaps, so your connection won’t be as good.
After every time you solder, with the soldering tip still hot you want to clean it off by wiping it against a damp sponge. You want to do this so you have a clean tip every time you go to solder. And now with the wires cooled down, inspect your soldering job.
You want to see the solder wick completely through the wires. You want the outline of the strands to be visible but you don’t want to see any bare copper.
Also you don’t want to see large globes of solder, because that indicates there could be a cold solder.
But what we’re looking at here is a perfect example of a correctly soldered wire. Alright with a good soldered connection now we’re on our last step.
Step 5 What we’re gonna do is we’re gonna take our heat shrink and we’re going to pull it up to are soldered area.
But before we slide it over the area that we just soldered i have a quick tip that’s going to make this connection last even longer and make it waterproof.
And that’s using silicone paste or dielectric grease.
All you have to do is get some silicone on there and then slide the heat shrink tubing over the top just like that.
So now you want to heat the shrink tubing with either a heat gun or a lighter and you want to start heating it from the middle and move outwards.
And this is going to force any extra silicon outwards. Now silicone or dielectric grease is perfect because it prevents moisture and it’s also an electrical insulator.
You can see it getting pushed right out and there you go. Look at that!! We just created a waterproof seal that’ll last a long time and the last thing i want to mention is one of the most common mistakes I see people make when they solder, and it’s called a cold solder. You never want to touch the solder to tip of the iron and drip it onto the wires. The solder doesn’t penetrate and it makes for a very poor connection.
Always add your heat to the bottom of the wire and add your solder at the top of the wire ,so the solder melts into the wire. And with that, now you know how to solder wires, so go practice on some wires.