This Tutorial’s main focus is to teach you how to solder properly and what tools are used in the Hand Soldering process.
Hand Soldering is a process used to repair, Modify or connect joints in a printed circuit board (PCB) assembly process. In hand soldering hot soldering iron tip heats the solder, and it flows inside the metallic surfaces to form a solid joint.
Mainly hand soldering is recommended in the prototyping, Installation, and repairing of PWBs in surface mount technology. For best joints, some soldering technique needs to follow.
Tools and Materials
Soldering is a process in which two or more metal items are joined together to make an electrically conductive strong bond between two surfaces by melting and flowing.
Here I will explain how to solder and the main soldering tools and accessories required to make a quality solder joint.
The quality of hand soldering mainly depends on soldering iron tip geometry, Selection of Flex, and instruction followed. Hand Holding is not as easy to work as normal people think.
Adopting some tools and techniques is required to get a minimum scrap rate, higher productivity, and better PCBA quality of rework consistency.
For more information, technical specs, and further details on soldering, check out the Wikipedia article.
1. Soldering iron
To do soldering, you need a good quality soldering iron or a temperature-controlled soldering station. Soldering iron good heat source that heats up and cools down very quickly and maintains a constant temperature.
Soldering irons soldering components are recommended as Low wattage (15-40 watt) soldering irons, but more powerful circuit boards (60-140 watt) soldering irons can be considered.
2. Solder wire
Solder wire is the main consumable material used in hand soldering. it comes in various thicknesses with leaded and lead-free versions. You use thin solder wires for normal electronic component soldering and thick ones when needed to solder large solder surfaces.
For more information, technical specs, and further details on solder, check out the Wikipedia article. I normally solder around .025″ wire in daily soldering jobs.
4. Other material needed for Hand Soldering
Apart from the above soldering tools, a few other tools are also used to make solid-quality soldering joints.
A list of other tools is a Soldering iron holder, a cleaning sponge, an Exhaust fan, Tools to work with wires like wire cutters, needle nose pliers, a wire stripper, etc., and Safety Goggles.
Getting Ready for Soldering
Once you are ready with all the tools and soldering material, you can start soldering the iron and let it heat up while prepping your materials.
The first thing is to Use the lowest possible soldering temperature (when using tin/lead solder, not higher than 360°С and when using lead-free solder, from 400°С to 425°С).
How to Solder – Step By Step
- Use the lowest possible soldering temperature (when using tin/lead solder not higher than 360°С and when using lead-free solder from 400°С to 425°С).
- Contact both terminals with a heated soldering tip and feed solder wire into the joints. Hold the tip until the melted solder flows into the joints.
- Clean the soldering iron tip with special tools (damp sponge, steel brush).
- Do not apply too much force when soldering (do not apply pressure on a board).
- The sponge must be damp, not wet. When pressing on the sponge, water must not pour around it.
- Turn off the soldering iron if not used for 5 minutes or longer.
- If you finish working with the soldering iron tip, clean it and tin it (apply the solder coating to the tip).
- Change a tip only by using a rubber pad intended for that purpose.1
Defects Due to incorrect use of soldering iron tips
Metal plating tips of soldering iron wear out over time. Plating life of soldering iron tip on a type of soldering application, types of flux and solder paste used, and the soldering skills of the operator.
Generally, the manufacturer does not give any guarantee of soldering iron tips. Usage of defective soldering Iron tips results in soldering defects.
How to Solder
Cracks: – Excessive pressure is applied with a tip to a contact area resulting in a tip bend. it will cause cracks in the tip coating. To avoid this problem, select the tip that best suits your work.
Non-wetting: – Oxidation of tip coating causes heat conductivity reduction due to formed oxides that will not allow proper wetting of molten solder paste. The best remedy to avoid such consequences is to frequently clean the solder tip with a damp sponge; use the lowest possible temperature, not recommend using active solder flux.
Corrosion: –Usage of Active solder paste at high temperature (>450 °C), the coating of the tip can possibly damage partially or completely. For remedy, use less active flux, use clean and damp sponges, and use solder that has an RMA flux type.