How to Solder | Complete Guide on Soldering Process
Learn How to Solder in this Complete Guide on Soldering Process.
Here we Learn How to Solder Properly and Neatly like a Professional.
What is Soldering?
Soldering is the process of joining two metals, generally leads of electronic components and copper track on Different Types of PCB (Printed Circuit Board) with the Help of a Tool such as a Soldering Iron and Alloy such as Solder Wire and Cleaning Chemical such as Flux.
The process is accomplished by quickly heating the metal parts to be joined, and then applying flux and solder to the mating surfaces.
The finished joint metallurgically bonds the parts forming an excellent electrical connection between wires and a strong mechanical joint between the metal parts.
How to Solder Neatly and Properly?
Neat and Proper soldering technique and quality of solder are the lifeline of any PCB Assembly. The secret to solder neatly and professionally is to use the right professional tool and good quality of consumables (wire, paste, bar, flux).
In electronics PCB manufacturing, assembly and rework, the metals to be joined are the leads of the electronic components (thru-hole or SMD) with the copper tracks on the PCB. The alloy used to join these two metals is solder which can be leaded with tin-lead (Sn-Pb) or lead-free with tin-silver-copper (Sn-Ag-Cu).
Tin-lead alloy is called leaded because of the lead present in it while the tin-silver-copper alloy is called lead-free solder because no lead is present in it.
The alloy is melted using suitable Tool or Equipment and it is then used to assemble the electronic components on to the PCB. A PCB or Printed Circuit Board after assembly of electronic components is called PCA or Printed Circuit Assembly.
Are Soldering, Brazing and Welding Same?
Few other terms such as brazing and welding is often linked with soldering. But one should remember that soldering, brazing and welding are different from each other.
Soldering is done using solder while brazing is done using a lower melting-temperature filler metal. In welding, the base metal also melts while joining two metals whereas this is not the case with soldering and brazing.
Terms to Know Before Learning How to Solder
Before we proceed to learn how to solder, let us understand some of the basic terms:
RoHS stands for Restriction of Hazardous Substances. The Law restricts the use of specific hazardous materials found in electrical and electronic products. The substances banned under RoHS are Mainly lead (Pb), mercury (Hg), cadmium (Cd), hexavalent chromium (CrVI), polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE).
WEEE stands for Waste from Electrical and Electronic Equipment. WEEE, also known as Directive 2002/96/EC, mandates the treatment, recovery and recycling of electric and electronic equipment. All applicable products in the EU market after August 13, 2006 must pass WEEE compliance and carry the “Wheelie Bin” sticker.
With NO Lead (Pb).
Best & Popular Lead Free Solder Composition:
- Lead Free Wire – Sn96.5/Ag3.0/Cu0.5
- Lead-Free Bar – Sn99.3/Cu0.7
- Lead-Free Paste – Sn96.5/Ag3.0/Cu0.5
Video: Types of Solder Wire
Static Electricity or ESD
Static electricity or ESD is an electrical charge that is at rest. This is mainly created by an imbalance of electrons that stay on a specific surface, or in the environmental air. The imbalance of electrons thus causes an electrical field that is capable of influencing other objects at a distance.
Video: ESD and ESD Protection
Flux plays a vital role in any soldering process. Flux removes any oxide and prevents oxidation of metals and hence helps in better soldering quality. There are basically three types of Flux used in Electronics:
- R Type flux – These flux are Non-Activated and are used where there is least oxidation.
- RMA Type Flux – These are Rosin Mildly Activated Flux. These fluxes are more active than R-Type fluxes and are used at places where there is more oxidation.
- RA Type Flux – These are Rosin Activated Flux. These are very active flux and are used at places that have too much oxidation.
Solder is the life and blood of any PCB. The quality of wire, paste or bar used during soldering process decides the life and performance of the Circuit Boards.
Different alloys are available but the real ones are those that are eutectic. Eutectic alloy is one that melts exactly at the temperature of 183 Degree Celsius. An alloy of tin and lead in the ration 63/37 is eutectic and hence it is called eutectic solder. Alloys that are non-eutectic will not change from solid to liquid at 183 Degree Celsius.
Solder is available in various forms:
- Solder Wire: These are called solder wire and are available in various combinations of alloy and in various diameters ranging from 0.2 to 1.5mm. It is basically used in hand soldering.
- Solder Bar: Solder bars are in the form of bar is sizes of .5 to 1 kg. It is used in Wave and Dip Soldering.
- Solder Preforms: As the name suggests, these are solder in predefined shapes and sizes. They can be circular, triangular, rectangular or square or in any other shape.
- Solder Paste: These are soldering in paste form. It is used in Reflow or Hot Air Soldering.
- Solder Balls: These are solder in the form of tiny balls in sizes ranging from 18 to 30 MIL. These are used in BGA or Ball Grid Array. Most of the tiny and slim gadgets have BGA.
PS: Alpha Cookson is a World Renowned and Trusted Manufacturers and Suppliers of All Soldering Ray Material.
There are two types of electronic components – Active and Passive Electronic Components.
- Active components are those that have gain or directionality. E.g. transistors, integrated circuits or ICs, logic gates.
- Passive electronic components are those that do not have gain or directionality. They are also called Electrical elements or electrical components. E.g. Resistor, Capacitor, Diode, Inductor.
Again, electronic components can be in thru-hole OR SMD (Surface Mount Devices or Chips).
Types of Soldering
Soldering can be done using any of the following types of soldering techniques or process:
Wave soldering process is used for mass soldering of through-hole Electronic Components to the PCB. Waves of Molten Solder is used in the Process, hence the name wave soldering.
Read: Wave Soldering Process
Reflow Soldering is done for mass production and is used for soldering of SMD components on to the PCB. Equipment and raw material needed for reflow soldering are – Reflow Oven, Reflow checker, stencil printer, solder paste, flux.
Hand soldering is done in small scale production and repair and rework such as mobile phone repairing.
Tools and Material needed for hand soldering are – Soldering iron, soldering station, solder wire, solder paste, flux etc.
Video: How to Use a Soldering Station
Another form of electronic components are BGA or Ball Grid Array. They are special components and need special soldering. They do not have any leads coming out , rather they used solder balls under the component.
Because the solder balls have to be placed under the component and soldered, soldering of BGA becomes a very difficult task. BGA Soldering need BGA Soldering and rework Systems and solder balls.
Read: BGA Soldering
Video: How to Reball BGA IC
It is a Technique of Selectively Soldering Electronic Components on the PCB that is Partially Assembled. Process Depends on the Type of Machine been used.
Video: Selective Soldering Process
- PCB Assembly Machines and Tools
- SMT Machine and SMT Machine Manufacturers
- Surface Mount Soldering Guide – SMD Soldering
- Mobile Phone Repairing Tools
- Printed Circuit Board: Design, Diagram and Assembly
- Buy Mobile Phone Repairing Tools Online
- Soldering Station Guide
- How to Clean and Tin Soldering Iron Tip