Solder the wire: How to Solder Wires Together: 14 Steps (with Pictures)

How To Solder Wires

Join wires together and more with soldering tips for beginners


Lee Wallender

Lee Wallender

Lee has over two decades of hands-on experience remodeling, fixing, and improving homes, and has been providing home improvement advice for over 13 years.

Learn more about The Spruce’s
Editorial Process

Updated on 03/22/23

Reviewed by

Larry Campbell

Reviewed by
Larry Campbell

Larry Campbell is an electrical contractor with 36 years of experience in residential and light commercial electrical wiring. He worked as an electronic technician and later as an engineer for the IBM Corp. He is also a member of The Spruce Home Improvement Review Board.

Learn more about The Spruce’s
Review Board

The Spruce / Kevin Norris

Project Overview

Learning how to solder wires is more important than ever. Homeowners are increasingly taking on repairs of home appliances such as dishwashers and refrigerators. When you know how to solder, small appliances like electric teapots no longer need to be discarded when they malfunction. With patience and a little practice, you can learn how to solder wires to circuit boards, metal connectors, and switches for repairs, as well as for fun projects.

In this simple project, you will solder together the exposed ends of two plastic-coated stranded copper wires. No special skills are needed to perform this task. Because the materials you need to solder wires are so inexpensive, you will have ample opportunities to practice on scrap wires before making your final solder joint.

Before You Begin

In lieu of purchasing separate soldering components, you may wish to buy a soldering iron station that includes a soldering iron, stand, and tip cleaner. Since the entire station plugs into an outlet, strain is reduced on the soldering iron cord. This is important to facilitate the delicate hand movements you make when soldering.

Leaded 60/40 solder, composed of 60% tin and 40% lead, has long been used for soldering. It is safe if handled properly. For the utmost safety, choose lead-free solder, composed of 99.3% tin and 0.7% copper.

Make sure that your work area is well-ventilated, especially when working with lead-based solder. Because the tips of soldering irons can range between 600 and 800 degrees Fahrenheit, work on a non-flammable surface; molten solder can drip. If working with lead-based solder, be sure to thoroughly wash your hands after working with the solder. Use eye protection whenever working with solder, no matter the type.

Equipment / Tools

  • Soldering iron
  • Soldering iron tips
  • Sponge and water
  • Soldering iron stand
  • Heat gun
  • Wire stripper
  • Eye protection


  • 60/40 rosin core solder
  • Rosin flux paste
  • Heat shrink tubing

The Spruce / Kevin Norris

How To Solder Wires

  1. Strip the Wires

    Strip away 1/2-inch of the plastic coating from the wires with the wire stripper. Try not to leave too much or too little of the plastic coating. Stripping away too little plastic coating will hinder soldering. Stripping away too much plastic coating will expose an excessive amount of copper wire and require you to use more heat-shrink tubing. Be sure to use the correct gauge on the wire stripper so that you do not accidentally cut away strands of wire.

    The Spruce / Kevin Norris

  2. Add the Heat Shrink Tubing

    Find the smallest diameter tubing that will fit over the plastic-coated wire. If you choose tubing that is too large, it will not shrink down to the correct size. In terms of length, the tubing should cover the splice, plus another 1/2-inch on each end. Slip the heat shrink tubing onto the wire and put it down the wire about a foot for now.

    The Spruce / Kevin Norris

  3. Join the Wires

    Gently flay the individual strands of wire. Push the wires toward each other, interlocking the strands. Loosely twist the meshed wires. If you twist the wires too tightly, the solder will not be able to penetrate. Yet the joint should still remain smaller in diameter than the heat shrink tubing.

    The Spruce / Kevin Norris

  4. Position the Wires

    Position the wires so that they are elevated over the work surface. Wires that lay flat may get stuck to the surface by the solder. Alligator clips or even household metal spring clamps can be fashioned to elevate the wires, if necessary.

    The Spruce / Kevin Norris

  5. Add the Rosin Flux

    Carefully rub a small amount of the rosin flux paste on the joined wires so that all of the copper is covered. Flux is a material made of either synthetic resin or pine tar resin. Solder wire usually has flux in its core, so though you may not need additional rosin flux to solder wires, it is highly recommended for its many benefits. Using flux will help draw the solder into the meshed wire strands for a cleaner, stronger bond and it helps to reduce oxidation.

    The Spruce / Kevin Norris

  6. Prepare for Soldering

    Plug in and turn on the soldering iron. Unroll about six inches of solder so that the end is exposed and ready to use.


    As the soldering iron heats, rub the tip across a wet sponge to remove any previous oxidation. For a new soldering iron heating up for the first time, this is not necessary.

    The Spruce / Kevin Norris

  7. Solder the Wires

    Touch the heated tip of the soldering gun to the wire joint. Hold the tip firmly in place for a few seconds to heat up the wire. Touch the exposed end of solder lightly to the wire joint. The heat should cause the solder to instantly melt and draw into the meshed strands.

    The Spruce / Kevin Norris

  8. Shrink the Tubing

    After the solder has fully cooled, slip the heat shrink tubing over the joint. Make sure that it is evenly positioned. Run the heat gun over the tubing until it constricts completely.

    The Spruce / Kevin Norris

Soldering Wires to Other Electrical Components

  • Rosin core solder is safest to use when soldering electrical wires; acid core is for plumbing (such as copper pipe).
  • Solder a wire to a circuit board by putting the tip of the gun between the wire and the board and letting the solder flow rather than trying to manipulate the solder.
  • Tin a stranded wire with solder first before soldering it to the circuit board.
  • Don’t try to “paint” the solder onto the wire or board with the soldering tip; solder can’t be spread around or moved.
  • Avoid letting too much solder puddle on the circuit board or you’ll risk solder touching neighboring circuits.
  • Use a clamp or vise to hold a circuit completely steady when soldering.

Solder Wire | Solders | Products made by Indium Corporation

  • Technical
  • Videos
  • Blogs


Related Solder Wire Blog Articles

Par 3s, Dollar Bills, and Fine-Diameter Cored Wire?

09 Feb 2022 by Robert McKerrow | View Bio

Indium Corporation manufactures cored wire that is nearly as thin as a human hair!

Read More

Automated Soldering Methods: What’s the Difference Between Robotic Soldering and Laser Soldering?

03 May 2021 by Robert McKerrow | View Bio

Laser soldering is making its way into the market and onto electronics assembly lines. What’s the difference between this method and iron-tip robotic soldering? Read to find out.

Read More

Solder in Medical Devices

18 Jan 2021 by Jenny Gallery | View Bio

The assembly of medical devices uses a wide variety of alternative soldering processes, of which the most frequently used solder products include paste, preforms, wire, spheres, and flux. Precision solder is required for these wearable, implantable, and industrial devices as they must be of high-quality and high-reliability, and be long-lasting. 

Read More

Soldering Iron Tip Temperatures Cannot Afford To Be Overlooked

26 Jun 2020 by Robert McKerrow | View Bio

Soldering iron tip temperatures are increasing under the thought that hotter settings perform faster to reduce cycle times. However, that is not always the case.  In fact, according to this wire supplier and other soldering iron tip manufacturers, it’s better to start as low as possible and work your way up to find the perfect temperature for your application.

Read More

Don’t Get Burned: How to Avoid Flux Charring

06 Jan 2020 by Robert McKerrow | View Bio

Charring is a common defect in hand and robotic soldering using flux-cored wire. Robert McKerrow explains what causes this and how to avoid it.

Read More

View All Blog Posts Close

Available Solder Wire Products

Indium Corporation manufactures solder wire for:
  • Cryogenic sealing
  • Hermetic sealing
  • Hand soldering and assembly
  • Rework
  • Die-attach applications
  • High-reliability soldering
  • Automated soldering
Solid Core Wire

Most of our alloys are available as solid core (no flux in the center). The most popular diameters are between 0.010”/0.254mm and 0.062”/1.52mm; however, SnAg and AuSn alloys are available in diameters less than 0. 010”/0.254mm.

Solid core wire is available in:

  • Pure indium and indium-based alloys
  • Bismuth-based alloys
  • SAC alloys
  • Pb-based alloys (including high Pb)
  • 80Au/20Sn
  • Pb-free alloys
Flux-Cored Wire

Flux-cored wire is generally used for manual soldering or rework, and is increasingly used in robotic soldering applications. It contains the flux in the center to facilitate the soldering process and eliminate the need for a separate flux. A variety of flux cores are available including no-clean, water-soluble, and halogen-free. Flux-cored wire is also used for soldering processes that do not involve electronics. Typical alloys for flux-cored wire include:

  • SAC alloys
  • Other Pb-free alloys such as SnAg, SnCu, and SnSb
  • Pb-containing alloys including SnPb and SnPbAg
  • High Pb-based alloys
  • Technical
  • Videos
  • Blogs


Related Blog Articles

Flux-Cored Wire

Indium Corporation is quickly becoming known as one of the highest quality, full line suppliers of flux-cored wire solder. Indium Corporation uses only “conflict-free” and grade A (per ASTM B32) metals, as well as other high purity metals for its flux-cored wire. Our materials have been tested and certified to meet IPC J-STD-004C and other relevant industry specifications, including the legacy military specification QQ-S-571f. Indium Corporation’s flux-cored wire is well known for its:

  • Void-free
  • Evenly layer winding
  • Low oxide shiny appearance over time
  • Non-offensive odor for the 800 series and 200 series fluxes

Learn More Contact Us

Indium & Indium Alloy Wire

The unique characteristics of indium metal make it an ideal solution for many soldering and sealing applications. As a wire, pure indium provides an excellent hermetic seal since it fills the imperfections in the mating surfaces. Pure indium also remains malleable at cryogenic temperatures so that sealing applications operating in harsh conditions are not compromised.

Contact us today to discuss your application and how our wire can work for you.

Learn MoreBuy Now Contact Us

How to solder with a soldering iron – how to learn to solder aluminum, copper wires with a soldering iron?

This article will help you learn how to properly solder with a soldering iron if you have not held one in your hands before. A soldering iron is a really necessary thing if you are a radio amateur, a system administrator, want to fix home electronics yourself, or if you want to learn something new and useful.

It is important to understand that if you need to solder wires in household appliances or solder a motherboard in a computer today, reading one article will not be enough. Despite the apparent simplicity, working with a soldering iron is almost an art, requiring care, experience and a steady hand. Before you solder something for a wire that has value, it’s worth a lot of practice on a consumable.

The principle of operation of the soldering iron

Understanding how a soldering iron works is not difficult. The heating element is heated to a high temperature (

300 and above degrees

). Soldering is the process of suction of a special substance (solder). It has a melting point lower than solder wire.

The soldering iron melts the solder, which fills all the micropores of the metal, interacting with them at the molecular level. When cooled, it “sticks” and forms a stable bond between the two parts of the wire.

Soldering iron and tools needed for the job

Answering the question “how to solder with a soldering iron”, it is necessary to touch on the topic of tools and consumables necessary for soldering. So, in order to solder correctly and efficiently, you will need:

  • The soldering iron itself
  • Special stand
  • Solder
  • Flux
  • Additional tools

soldering iron

There are many different models needed to solve a wide range of technical problems. But the main criterion is power. By power, they are divided into several types:

  • 3-10 W.

    These are the smallest models. They are designed for soldering the smallest and most sensitive microcircuits.

  • 20-40 W.

    Belong to the category of “household” or amateur radio. With their help, you can both solder a wire, and a transistor or other part.

  • 60-100 W.

    If the wires to be soldered are very thick, this type will do. It is often used by car enthusiasts or professional mechanics

  • 100 W

    and more. With such a soldering iron, you can solder both a thick wire, and a pan or even a car radiator. They are used only by professionals, and for obvious reasons are not applicable in everyday life.

If you plan to solder radio components, it will be enough

25 cotton

tool. To solder a regular wire, the power should be enough, but for everyday use it is worth choosing a model in

35 W

and higher.

Stands are often sold as a set. They not only keep the worktable free of solder stains, but also allow you to always control the position of the tool. In work, it should be on the edge of the table. It is important to keep an eye on the network wire.


In this special low-melting alloy, as a rule, substances are used:

  • Tin
  • Lead
  • Cadmium

Or any other metal with a suitable melting point. The most fusible have a melting point

up to 80 degrees

and the most stable

over 900.

In everyday life, it is recommended to use brand solder

POS 61.

The most convenient type is a thin wire.


This is the name of a special substance that acts as a link between the solder and the metal of the wire. It aids solder adhesion and successfully protects it from oxidation and aids in degreasing. The most popular brand is

LTI 120.

If necessary, it is done independently. To do this, it is enough to dissolve the rosin in alcohol (approximately

60 to 40%

) and shake well.

Additional tool

To conveniently and safely solder with a soldering iron, you should acquire items:

  • Wire cutters. They bite off the wire, remove the insulation, support the part during operation
  • File – for cleaning the heated part of the soldering iron
  • Scalpel with tweezers. They will help not to burn your fingers when working with small parts.

Getting Started

A new soldering iron must be cleaned and tinned. Should be plugged into the network.

for 15-20 minutes.

At the same time, the factory grease often begins to burn out, and the tool itself may smoke a little, this is not scary.

After warming up, carefully clean the working surface with a file, after which it is immediately dipped in solder. It is important not to let it oxidize. Now the tool is ready to work.

It is important if the tip of your tool is made of cermet. It cannot be processed with a file. To do this, there is a special damp cloth, and it needs to gently wipe the surface.

How to solder a wire: the process

It is very important to prepare the surface. It should be free of foreign matter such as grease, paint varnish, insulation residues. The success of all work depends on purity. If there is something, you should carefully clean it with a scalpel and wipe it so that there is no dust left.

Next, you take some solder with the tip and carefully solder in the right place. This is not a very difficult process, but it requires a “stuffed” hand, and the very first time you are unlikely to get a beautiful and neat soldering.

While working, it is worth remembering a number of rules:

  • Spike must be fast
  • If it didn’t work out to solder the wires right away, you should let them cool before the second attempt. This is doubly true for radio components or microcircuits.
  • The end of the tool should be applied with the entire surface, the process will be most effective

How to solder wires more reliably? You should twist them before starting the procedure. After cooling, they are isolated with electrical tape to avoid short circuits during operation.

A good adhesion is distinguished by its brilliance, even layer and the absence of any cracks. Then it will last as long as possible, and you will not have problems with the device.


How to solder with a soldering iron and not get burned? Safety precautions must be followed. Working with a soldering iron is not the best time to try your luck with breaking safety rules. There are some simple tips:

  • Free the work surface from foreign objects
  • Remove unnecessarily curious children and animals from the room
  • Watch the cord – hitting it with your foot or hand, there is a risk of burns
  • If there are strangers in the room, warn them that you are working with the soldering iron turned on.
  • Flux – very little. If used too much, it can splatter on your hand, and in the worst case, right in your eyes.
  • Each time you should take solder no more than

    2 rations

    . If you overdo it, it can drip on the table, hand, or even worse – on the soldered microcircuit.

By following these simple rules, you will save yourself from extremely unpleasant consequences. If you take your work seriously and do not leave the soldering iron unattended, there should be no problems.

Solder wires well

The further operation of the entire device depends on how the wire is soldered. Experienced craftsmen give a number of tips for high-quality and reliable soldering:

  • If there is not enough solder, it will not be able to properly fasten the parts and fill all the gaps.
  • With an insufficient amount of flux on the sting, the soldering point turns out to be heterogeneous and uneven, which negatively affects the result. This can be with a heated tool, then the rosin evaporates before the end of soldering
  • When there is too much rosin, it can splash out and touch adjacent contacts or wires, and in the worst case, get on your hand.

With experience comes the ability to heat the soldering iron to the correct temperature and use only as much solder as needed. With a perfect balance, the solder automatically takes the desired shape and flows around the contacts correctly. This is exactly what we need to strive for.

It is best to use soldering irons with a thermostat. Then it is easy to maintain the desired temperature, which has a positive effect on the process and the result of the work. A soldering iron without a regulator can quickly overheat, and its tip can blacken from oxidation. Then it has to be turned off periodically. It is very difficult to maintain the desired temperature, and the soldering is of insufficient quality.

How to solder with a soldering iron?

The best way to learn how to do anything is to practice. Soldering is no exception. There are a number of exercises that help to master this, of course, a complex, but useful tool.

You should take a bare or insulated wire (to practice stripping) and cut it

into 12 identical pieces.

To make them not too small, the optimal length is

30-40 centimeters

(before cutting).

After cutting, you should take a soldering iron and make a cube out of these blanks, using only a soldering iron and pliers. This will allow you to get a feel for the instrument and get used to its use. Then the finished cooled cube should be taken in the palm of your hand and clenched into a fist. The work is satisfactory if the adhesions remain intact. This can be practiced to keep your skills at a high level, even if you are experienced and confident.

The second method of soldering iron training requires thin wire and stripped cable. It must be wrapped around the wire, and then carefully soldered using a soldering iron and pliers. It should be practiced until you can solder wires qualitatively the first time. After that, it is worth starting normal responsible work.

Regular practice will allow you to achieve significant progress in soldering very quickly. Soon you will be able to fix the radio, wiring (observing the rules of caution) or other household appliances yourself. But before that, it is worth entrusting this matter to specialists so as not to risk expensive items.

How to solder with a soldering iron. Soldering wires, transistors, LEDs.

electrical, alarm, video surveillance, access control (ACS), engineering systems (ITS)

In order to solder well and correctly, you should know a few basic points that characterize the process of soldering with a soldering iron, moreover, it does not matter whether it is electric or gas.

Here we will consider how to solder POS with solder (an alloy of tin and lead, depending on the proportions of the content of these metals, the melting temperature of the solder changes).

Solder can be used to solder various metals together. The easiest way to solder copper, brass. Somewhat more difficult – steel, soldering other metals, such as aluminum, is possible, but requires the use of special fluxes and additives.

Let’s just talk about the flux.

This is a substance that prevents the oxidation of the metal during soldering.

The simplest and most famous flux is pine rosin. It is used in lump or liquid (alcohol solution) forms for soldering copper, brass.

It is a passive flux, that is, it only prevents the metal from oxidizing when it is heated with a soldering iron, but it cannot remove the existing oxide film (for this, various active fluxes or trivial mechanical cleaning are used).

Removing the oxide film is a mandatory process during soldering, since the solder melted with a soldering iron must wet the metal surface, oxides prevent this, just as fat prevents any surface from wetting with water. I think, when considering specific examples, everything will be clear to you.


Before soldering, you should properly prepare the soldering iron. Its tip should be evenly coated with solder. See photo:

This is what a “dirty” sting looks like. Correctly soldering such soldering irons is very difficult.
From a cold soldering iron, remove with a file all the dirt to pure copper (the material of the soldering iron tip is copper).
It should look like this.
We heat the soldering iron, successively touching the rosin and solder (several times), we achieve a uniform coating of the working part of the soldering iron with solder.
The result, reaching which you can solder.


We clean the wire
We tightly twist its cores (for stranded wires).
Having previously taken the solder on the soldering iron, heat the rosin, immerse the wire in the melt, evenly distribute the solder over the surface of the conductor with a soldering iron.
The result is a tinned conductor.
If you need to solder the leads of semiconductor elements (transistors, diodes, etc.), then, in order to avoid overheating of the crystal, soldering should be done quickly, using a heat sink (tweezers, for example).


You can solder the wires together in various ways, for example, by laying pre-tinned wires on top of each other, heat them up with a soldering iron until the solder melts.
This is the result.
Stripped wires can be pre-twisted.
Solder the twist as in tinning. By the way, solid rosin is used in all examples.