Soldering Guide - How to solder ?

What is Solder?

A Solder is a metallic alloy used to join a pair of metallic surfaces into one. Joining metal parts together, by allowing a molten metal alloy to flow around them is called soldering.

When the solder cools and solidifies, it provides an excellent electrical connection between the parts, along with a little mechanical strength.

This is a craft that should be honed by both experts and hobbyists similarly and is required in the building, repairing, and modifying of electronic components.


It would be best if you always worked in a well-ventilated area. Avoid breathing in the fumes, as prolonged exposure to solder can cause health problems.

While some “experts” disagree, we advise that you always protect your eyes.

Safety glasses are a minor discomfort and an inexpensive investment for a lifetime of good vision.

How to Solder: Overview

Equipment: Basic Tools

Soldering iron is the one tool that you will always need when soldering. A soldering iron between 25W and 30W recommended for minor electronics work.

Higher wattage soldering irons are generally not used for soldering small electronic components.

You will also need some solder, a rosin core solder, preferably with a small diameter recommended. The solder will be composed of 60% – 40% lead, and cores of rosin “flux” which supports the molten solder to flow more smoothly over the joint.

A thin solder with a small diameter makes tinning the exact amount of solder that you will need much more comfortable. It’s regularly a great idea to have a small wet sponge to clean and cool the soldering iron tip.

Most soldering iron holders come with a sponge attached to its base. Refer to the soldering tools page for detailed information regarding tool selection.

Component Preparation

Before you start with the process of soldering, you need to make sure that all of the required parts to be soldered are free from grease, oxidation and other contamination. Otherwise, you will find yourself battling with lots of hot soldering running throughout anywhere you do not need them to be.

A dirty surface can also cause the solder to not join well to the surface, and beginners can make the error of overheating the elements while they attempt to force that solder to hold.

What will generally result in irreversible destruction and will require you to replace the elements. It’s essential to realize how to prepare the parts to be joined.

Component Tinning

Both soldering connections must be tinned before you attempt to solder them. This coats or fills the wires or connector contacts with solder so that you can melt them together.

For example, if you are soldering a piece of insulated wire, you should use a wire stripper tool to peel off the tip of the insulation so you can expose the copper wire within, and carefully cover it with the solder.

You must also tin the tip of the iron to help conduct heat to the components.

Applying Heat and Solder

While you are using the tinned soldering iron, you are now ready to heat the components to be soldered. The purpose of the soldering iron is not to transfer a glob of solder, but to provide heat.

Many novices wrongly attempt to use the soldering iron to shape the joint. Solder will naturally flow to the parts that are heated, and do not require you to form the joint with the soldering iron tip.

Rest the iron tip on both the component lead and the circuit board. It’ll barely take a few seconds to heat the components depending on the surface area.

Once you have heated the component and the circuit board, the solder will naturally flow towards the heat. Attach the tip of the strand of solder to the heated component lead and the solder pad on the circuit board, but not to the tip of the iron.

At this point, the solder will flow freely around the component lead and the pad. Once the surface of the pad has been completely coated, you must stop adding solder and quickly remove the soldering iron.

Do not move the newly formed joint for a few seconds until the solder cools down and becomes solid.

Cleaning and Finishing up

It would be best if you always clean the soldering iron tip after each soldering session. There are solutions mainly intended for that, but a damp sponge will work just fine.

The main idea is to clean the soldering iron tip each time you finish a solder joint. That is to say, and you’ll be cleaning the tip several times per session if your project requires you to form multiple solder joints.

To clean the solder off a circuit board, you should use a solder wick. First place the wick on the joint or track you want to clean up and apply your soldering iron on top. The solder will heat and melt and will be drawn toward the wick.

in this stage, the wick will fill up, now gently pull that wick over this joint that attached to your iron, so the solder will run through it as it passes.

Soldering wire