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Lets start Soldering:
Soldering is one of the basic skills needed for to test and assemble electronic circuits. Every electronic component has some terminals to conduct bias and also to hold that component on circuit board. Before learn to soldering we have understand about the basic tools of soldering. The first one is Soldering Iron, different kind of soldering irons with different temperature and watts ranges are available in the market (also SMD soldering iron), depends on our need we have to choose one among them. Here we considered basic and hobby need so we taken 25 watts soldering iron.Soldering lead is flexible metal alloy and it has lower melting point and this solder lead used for to joint two deferent metals like component terminal and PCB track. Next the soldering flux paste it is used to direct the flow of solder as attractive bead.
Step 1: De-soldering Wick
This de soldering wick is very useful when the soldering goes wrong. We can use this copper wick to remove solder metal from the circuit board. Sometimes professionals are use desoldering gun.
Before soldering electronic components rub and wipe the solder tip. Because when we use soldering iron due to heat dust the tip becomes dirty, if we solder the component with same dirty tip solder metal will not hold the terminal strongly.
Step 3: Follow These Steps to Solder the Component on Circuit Board.
Step 1. Place and insert the required component pin in circuit board. Before that bend the components pin correctly for perfect soldering.
Step 2. Place the PCB (Circuit board) to you convenience, like the picture shows.
Step 3. Apply the soldering flux paste on place of soldering.
Step 4. Use the heated soldering tip to pickup soldering lead as required (do not take lead over than required).
Step 5. Do the soldering on the correct position as shown in the picture.
After completing above steps check your soldering by looking and slightly shaking your soldered component (Be very careful because recently soldered component or soldered material may be very hot).
Step 5: Use De-soldering Wick
If the soldering goes wrong use de soldering wick to remove the soldered material from the PCB.
By the way can remove the wrong or defected component and resolve issue.
(Please note that Soldering process is dealing with very hot temperature material, be very careful while handling)
Step 7: Handle With Care
description source: http://www.theorycircuit.com/know-before-soldering/