Proper Soldering Techniques Explained

Proper soldering techniques start with your choice of soldering iron and solder. The simplest kind of soldering iron plugs directly into a socket, and when turned on, heats up to a standard temperature based on how it is made. These cost a fairly small amount. They are fine for occasional work and small joints. Then there are temperature-controlled irons with some kind of built-in thermostatic control. These cost a good bit more. For the professional, or hobbyist who does a lot of soldering, there is the soldering station. This is a control unit that allows you to precisely control the temperature of the soldering iron. You may have to buy the iron separately. These are the most expensive, excluding outdoor gas-powered systems.

Solder is a soft alloy with a low melting temperature. Usually it is made of tin and lead. Lead-free versions are being mandated in many countries. Solder contains a core called "flux," which de-oxidizes the surface on which the solder is placed. Rosin flux is used for electronics, and acid-based flux is for for soldering metal pipes. Make sure to use the correct kind.

Preparations

To keep the circuit board in place, put in it a soldering frame or a small vice. Clean the area where solder will be applied. A new soldering iron tip needs to be "tinned," which means coating it with solder. When you start work, get a little melted solder on the tip, which is called "wetting." This creates a good flow of heat into the area being soldered. You will probably drip solder, so have something placed to catch it. Warm the iron up before you start. Make sure there is ventilation so you don't breath the smoke.

Heat the Base

Touch your hot soldering iron tip to the base area where the solder will go. Do not touch the iron directly to the solder. When the base metal is hot enough, touch the solder to it. It should flow into place. The base metal has to be hot. Putting solder on a cold area will not create a good connection.

Don't Give it the Cold Solder

A "cold solder joint" is a bad joint, caused by not enough heat being applied. It can also happen when the joint is moved before it sets. This joint may be brittle or it may not conduct electricity well. Sometimes they are visible, looking grainy and dull instead of shiny. This is not always true. If your circuit doesn't work, you have to find the cold solder joint and fix it. Simply reheat it and apply a little more solder.

Flux Cleaning

Extra flux should be cleaned off, or it may ruin your circuit. Methyl hydrate or a commercial solvent made for this purpose will take it off, then wipe the area with a rag.

Once you gain the skill to solder correctly, you will be able to make and fix electronics, or enjoy other hobbies like model train and airplane construction. This skill makes you