Having a good understanding of the best soldering techniques is a useful and fundamental skill that all makers must master. Here, we will be outlining the fundamentals of soldering stations, soldering irons, safety tips, desoldering, and solder types. Whether you decide to build a robot or you work with Arduino, it is very important that you know how to solder.
What is Soldering?
Imagine you need to take a specific electronic device apart containing a circuit board, then you will see some soldering components that have been attached with the help of some soldering techniques and soldering equipment. Now, soldering refers to the process necessary when joining at least two electronic parts. This is possible by melting solder about and around that connection.
Also, solder is known as a metal alloy and anytime it cools, it helps in creating a strong electrical bond. Although soldering can help create some permanent connection, you can reverse it by making use of a desoldering tool.
What are the Soldering Tools?
One great thing concerning learning ways of soldering is that to begin, you don’t need too much. Here, we will be outlining the important materials and tools necessary to achieve success in your soldering projects and jobs.
Soldering iron is referred to as a specific hand tool, which plugs into an AC outlet of 120v. It also heats up, so as to melt the solder surrounding the electrical connections. Soldering irons are a very important tool for soldering. You can find it in different forms and variations like gun form or pen form.
For all beginners, it is advisable that you work with the pen form soldering iron that falls within the 15W to the 30W range. Majority of soldering irons also feature interchangeable tips, which is useful for any soldering applications. Also, when making use of any soldering iron type, be very careful. This is because it can become extremely hot, heating to about 886’F.
Soldering Iron Tip
Found at the end of majority of soldering iron is a part that is interchangeable called soldering tip. This soldering tip comes in different variations and they also come on different sizes and shapes. Each soldering iron tip is useful for a unique purpose. It also provides a great benefit over another. Two main soldering iron tip that will serve your electronic projects include chisel tip and conical tip.
For chisel tip, it works best for soldering wires, as well as other larger components. This is due to the broad flat tip it features. On the other hand, conical tip is useful for precision electronics soldering. This is due to the fine tip of the iron. It has a pointed end, and can deliver heat to very small areas, without having to affect its surroundings.
This version is a more advanced type of the basic soldering pen. Note that, if you have much soldering to do, then having a soldering station is necessary because it will provide you with more control and more flexibility.
The soldering station offers a major benefit, which is its ability to adjust the soldering iron temperature or soldering temperature precisely. This adjustable temperature soldering iron is great for different projects. Also, these stations help in creating a much safer workplace, because some feature alert settings, temperature sensors, as well as password protection to ensure safety.
Making use of sponge ensures that the tip of the soldering iron is kept clean. It achieves this by getting rid of whatever oxidation forms. Furthermore, tips having oxidation tends to turn into bland and doesn’t accept lead free solders the way it did when new.
Furthermore, you can use a wet sponge; however, using a wet sponge drips the soldering tip temperature temporarily when it is wiped. The much preferred alternative to the wet sponge is a brass sponge.
Soldering Iron Stand
This iron stand is basic but useful and important to have. The iron stand prevents the tip of the iron from touching the flammable materials or leading to accidental injury to the hand. Majority of soldering stations feature this and also comes with a brass sponge to clean the soldering tip.
This is also called the third hand. This is a device featuring at least 2 alligator clips. At times, it features a magnifying light/glass attached. The clips assist by firmly holding those items you want to solder as you use the solder and soldering iron. This tool is very helpful in the makerspace.
You may not be used to this, but when soldering, it is a very good idea to work with safety goggles. This is because little molten solder bits can fly out when feeding inside the solder. If this molten solder gets into the eyes, it won’t give a good feeling.
This metal alloy material is usually melted to help in creating a strong and permanent bond in between the electrical parts. This comes in lead free solder and lead solder variations, with the most common of then having 0.062 and 0.032 in diameter.
There is a material in the solder core called flux. This helps in improving the mechanical strength and the electrical contact. Concerning electronics soldering, rosin core lead free solder is the most frequently used. This lead free solder type is made of a copper/tin alloy.
You can make use of a rosin core leaded 60/40 solder. This means 60% tin and 40% lead. However, this is now less popular as a result of health concerns. If you are making use of leaded solder, ensure that there is proper ventilation and wash your hands properly after use. When purchasing lead free solder, ensure that you don’t make use of acid core solder. This can damage your components and circuits.
As we have mentioned before, solder comes in different diameters. 0.062” is known as the thicker diameter for the solder and it is great for soldering larger joints quickly. However, when soldering small joints, it can be difficult. This is one reason why it is nice that you possess both sizes for different projects.
What are the Soldering Safety Measures to Take?
Now, you know the materials and tools necessary for soldering. It’s time you learn how to stay safe when soldering.
Know that soldering iron temperature can reach 800 degrees Fahrenheit, therefore it is important to know the soldering temperature all the time. Also, we recommend that you always make use of a soldering iron stand. This prevents damage or accidental burns.
Ensure that the area you are soldering is well ventilated. When heating solder, fumes are released, which could be harmful to the lungs and eyes. This is where a fume extractor comes in. This is a fan featuring a charcoal filter absorbing the solder smoke.
Also, another great idea is using protective eye wear. This is necessary for accidental hot solder splashes. Lastly, ensure that after soldering, you wash your hands, most especially when using lead solder.
Tinning the Tip of the Soldering Iron
Before soldering begins, there is a need to prepare the soldering iron simply by tinning of the soldering tip using solder. With this, it transfers heat from that iron to whatever you wish to solder. With tinning, you will also be able to reduce wear and protect the soldering tip.
- Start by ensuring the tip is properly attached into the iron. Also, make sure that it is well screwed into place.
- Turn the soldering iron on and allow it to heat up. For those having a soldering station featuring an adjustable temperature control, ensure you set it to 752 degrees Fahrenheit or 400 degrees Celsius.
- Next, wipe the tip of the iron on a wet or damp sponge, and then use it to clean it. Then, wait for some seconds to ensure the tip heats up again.
- Use one hand to hold your soldering iron, and the use the other to hold the solder. Next, touch your solder to the iron tip and ensure there is an even flow of the solder around the tip.
Also, tin your iron’s tip after and before every soldering session. This helps in extending its life. In the end, all the tips will definitely war out and you will have to replace when it is pitted or rough.
Steps on How to Solder
In order to explain what solder is, let’s demonstrate using real world application. Here, we will be soldering an LED to circuit board.
Mount your component
Start by the insertion of the LED leads to the circuit board holes. Then flip over the board and then bend these leads outward at an angle of 45 degrees. This helps to ensure a better connection for the component with copper pad. Also, it ensures it doesn’t fall out when you are soldering.
Heat the Solder Joint
Turn on the soldering iron and if it features an adjustable heat control, you can set it to about 400 degrees Celsius. Then, touch the iron’s tip to the resistor lead and copper pad at once (same time). For three to four seconds ensure that the soldering iron is held in place. This ensures the heating of the lead and the pad.
Application of Solder to the Solder Joint
Jeep holding your soldering iron on the lead and copper pad and then touch the solder onto the joint. Make sure you prevent the solder from touching the iron tip directly. You want this joint to be very hot so that solder melts whenever it is touched. When the joint is very cold, this results in a bad connection.
Snip the leads
The next step is to take out the soldering iron, then allow the solder to cool down on its own (naturally). Avoid blowing on the solder; this will lead to a bad solder joint, and what we want is to create great solder joints. Immediately it cools, you can go ahead to snip that extra wire from the leads.
Furthermore, a good solder joint is shiny, smooth, and has a similar shape to a cone or volcano. You wish to have more than enough solder to help in covering the entire solder joint. However, take caution to ensure that the solder isn’t too much causing spills or a ball close to a solder joint or lead.
Important points when soldering on Circuit Boards
You need more attention and care when soldering on your circuit board. However, you can still do this. From your spare resistors and LEDs, you can push some leads through some of the open holes present in any circuit board. You can then solder the leads to the bottom part of your circuit board whereby these electrodes can push through. We call this plated through hole soldering.
During the soldering of leads in circuit boards, you should heat the contact of the metal on the board coupled with the lead. When you apply too much heat, this could cause damage on your circuit board.
How to Solder Wire
The next step of our article is to explain to you the best way of soldering wire together. This process highly recommends that you make use of helping hands as well as other clamp device types.
Start by taking out the insulation from the end of the solder wires that you’ll be soldering together. Note that, if this thin wire becomes stranded, you twist these strands together using your fingers.
Furthermore, ensure that the soldering iron is properly heated and then touch the soldering iron tip to the end of any of the solder wire. For three to four seconds, hold it to the solder wire.
Ensure the iron remains in place and then touch your solder onto the braided copper wire till it is fully coated. Then continue the process on the second solder wire.
Hold both tinned solder wires on the top of themselves and then touch that soldering iron to both soldering wires. The soldering process ought to melt that solder and then coat the two solder wire evenly.
Next, remove the soldering iron, wait for some seconds and then allow that soldered connection to cool and then harden. Also, make use of heat shrink in covering the connection.
Soldering Using a Lighter
From what we have said so far, soldering has to do with joining things in order to establish a connection. If the necessary tools for soldering are absent, and you still wish to solder, them can try something called bare bones soldering.
Bones soldering is very useful in cases where you are lost on a desert. Here, you need to repair your headphones to help you watch as the sun goes down. All you need to do is to pick some wire pieces and then strip them using your teeth; you can use your molars. Next, grab the insulation using your teeth and then sever this insulation a little, then pull on that wire.
Working with the braided wires make things easier, and you will need some practice to help apply the best tension so that you won’t end up ripping the wire apart.
After stripping and twisting the wires together, you get a lighter and some solver and then heat up the wires you wish to join. It took the same time for the lighter to heat the wires up as it took the iron. Then you can feed some solder in the joint and continue to heat the wire till you see that things have smoothened out. Next, turn the flame off.
This works perfectly fine, just the same way you use an iron. Though it is not as easy as the soldering iron, but it does the job for sure. There are cases as well where people have used matches to solder the wires.
What is Desoldering?
There is a very important think to know concerning the use of solder. The fact is, you can remove it using a technique called desoldering. This is important in cases where you need to take out a component or make corrections to an electronic circuit. To help in desoldering the solder joint, there’s a need for solder wick. This solder wick is also called desoldering braid. Below are the steps necessary for desoldering.
Place just a piece of your desoldering braid on the top of the solder or solder joints you wish to remove.
Next, heat the soldering iron, and then touch the braid top’s tip. This helps in heating the solder underneath. This is then absorbed in your desoldering braid. The next step is to take out the braid and then see that the solder is removed and extracted. Take care when touching your braid during heat because it can become hot.
You can work with this also. If you wish to take out much solder or excess solder, then use solder sucker. A solder sucker is a mechanical vacuum with a handle that helps to suck up any hot solder just by pressing a button.
In order to use, press down the plunger at the end of your solder sucker. Next, heat that joint using the soldering iron, then place the solder sucker tip over your hot solder. Next, press its release button to help in sucking the liquid solder up. To ensure the solder sucker is empties, press the plunger down.
What is Flux?
For your soldering, think of a prepping agent and flux. When you join the surfaces of two metals together using solder, then there is a need to have a strong metallurgic bond available. This prevents the solder joint from breaking loose and the electrical continuity won’t fluctuate with temperature, mechanical, as well as other stresses.
Also, flux helps in reducing any oxidation, which may be included. It also etches that surface slightly to help in promoting wetting. Wetting refers to solder flowing over the contacts and soldering tip surfaces.
This is very necessary for soldering
Types of Flux to Use
One great choice when soldering is the no clean flux. You can leave the light flux residue on the board, or remove it using any flux remover. The rosin activated flux helps in providing great solderability through different applications. The best thing is removing the residue when done with aesthetics soldering and to prevent possible corrosion.
Water soluble flux is active and it is engineered to be taken off with ease using DI water. You can also remove it using IPA – Isopropyl alcohol. Cleaning of water soluble flux is very necessary. This is because of their highly corrosive nature.
In addition, you may see other options for zero halogens or halogen free. These classifications work for companies having green initiatives and need to work with halogen restrictions as a result of customer or regulatory restrictions. Examples of halogens include astatine, bromine, iodine, and fluorine elements.
Also, these can appear like trade-offs such as cleanability. Therefore, if you don’t need to get rid of halogens during the process, then you can remain with the standard fluxes containing halogens.
Is Adding Extra Flux Necessary During Soldering
When you are soldering simple connections, such as 2 wires, the flux present in the flux core solder is more than enough. However, when dealing with a very complex surface mount soldering technique, such as drag soldering of multiple leads on the surface mount component, then you may need to add more flux.
You can activate and consume the flux when it initially flows from that core. Note that when working on the solder further, such as drag across the multiple leads, then there is a risk of having cold joints as well as bridging without more flux. Though, more flux needs to get removed, most especially if you don’t activate it fully.
The fastest way of learning how to solder or becoming an expert here is to practice using lots of circuits. You can get yourself soldering kits immediately to help with your practice. Another thing you can do is to find some circuits and then solder them to a stripboard. Let us know if there are questions on your mind concerning soldering.