What are the Best Practices of PTH Soldering?

The term ‘Pin through Hole’ refers to the process through which the legs or leads of electronic parts are inserted in the PCB. They are also soldered in place with a soldering process. It results in the formation of the solder joint fused with the PCB. On the other hand, SMT components are soldered only to the PCB surface. Technology is highly useful when manufacturing products like TVs. You can also find it in older computer models that need strong interconnections between circuit boards. Some PCB manufacturing projects involve using both PTH Soldering and Surface Mount Technology.

Know About The Solder in PTH Soldering Processes–

Solders are metal alloys for joining metals together. Especially electronic manufacturers need to use solders. There are different types of solders used for joining metals. Every solder type has a unique composition, core, and form. The melting point will be low compared to the metals it joins together. The soldering process involves mounting a particular component to the PCB. Assemblers use solders for the joint to stick to the board. Electronic assembly mainly needs lead-free and lead solders. 

So, soldering skill is highly important for professionals in the world of electronics.

Difference Between Lead-Free And Leaded Solders

Leaded solder, also known as SnPb solder, is a metal alloy containing lead and tin (base components). The leaded solder is preferable for some reasons.

Wetting joints: Leaded solders are highly useful for wetting joints. They help with electrical connections for PCB pads and leads.

Cooling: The cooling process for the leaded solder is slower when compared to other metals. It reduces the risk of joint cracks. 

Melting points: While other metal alloys have a melting range, lead solders have a particular melting point. So, it becomes easy to conduct an automated process for PCB assembly. As the melting point is low, there is a minimal chance of damaging electronics.

But, lead is detrimental to the environment and human health. Lead exposure may lead to different health issues, like reduced fertility and memory loss. 

On the other hand, lead-free solders have replaced traditional SnPb solders. The composition of the lead-free solders has a varied percentage of tin, copper, zinc, nickel, silver, bismuth, and antimony.

The main goal is to use high-quality solder alloys that combine with trace metals to provide good mechanical properties. 

The melting point of lead-free solder paste is around 422°F. Though professionals need to choose different soldering practices under high temperatures, joints created with lead-free solder are highly reliable. 

What are the Most Important PTH Soldering Tools?

Professionals need to use different tools for their soldering projects.

Soldering Irons

The soldering irons of different models help you solder small components and connections. There is no need to use bulky, costly tools. While using the soldering irons, you choose 25W. Underpowered irons will make the project costly because of damaged and ruined components. 

 Besides, underpowered irons take much time to heat joints and overheat the components to be soldered. Professionals choose the soldering tools for electrical components and metallic elements. 

Soldering Wick

Soldering wicks are the de-soldering tools used for rectifying mistakes. They intertwine copper wires together, and the heated wires help you alter the soldered joints. The application of heat to the tip causes the solder to melt easily. After covering the part of the wick with solder, it is to be removed. You have to repeat the process to eliminate the solder. 

Magnifying Glass–

A magnification device is a highly essential tool, as precision is a vital factor for soldering projects. It helps you clearly see every part of the electronic component. That is why a magnifying glass lets you avoid mistakes in the project.

Wire Cutters

The PTH soldering process involves dealing with different wires that have to be cut. Thus, wire cutters are the best tools to cut along the leads of the component.

Flux

Flux is a type of chemical agent that helps with the flow of lead-free solder. This tool lets you dab the liquid flux with different components to form solder joints. It is highly useful for cleaning and removing water-soluble flux on the board. 

Describing the PTH Soldering Process–

Through-hole soldering is a comparatively easy process because the leads and holes of components are bigger. You should collect high-quality soldering tools and materials. Make sure you can comfortably grip and operate the soldering iron. You can now use the solder formed for PCBs. The rosin core solders are perfect for maintaining consistency in the flux.

Besides, the metal surfaces must be contaminants-free and clean. In some cases, it is essential to use industry-standard cleaners. There are some steps for PTH soldering.

• The first step involves melting the solder at the tip of the soldering iron. The step lets you conduct with some heat. 
• By inserting the component leads through the hole of the board, hold the iron’s tip properly against the lead and the hole.
• Place the iron properly to heat the component leads and hole thoroughly for a few seconds. However, the board should not get burned.
• You can then feed some solders into the soldering iron’s tip. The solder will fill up the hole and create a filet. When it melts, you can remove the iron and allow the joint to become cool. Make sure you have not stressed the connection until you have cooled it properly. It results in the formation of good solder joints.

The de-soldering process lets you learn PTH soldering. So, you can salvage and upgrade for soldering and de-soldering purposes. If you do not know whether newly developed solder joints can make electrical connections, you can use multimeters to conduct a continuity test. However, quality soldering also depends on the way you have placed the parts.

Most Common Issues with PTH Soldering

Components used for PTH are bigger than SMD components. Depending on your PCB design and your own skills, you may face some challenges in the PTH soldering project.

In some cases, it is not easy to place the PTH components onto the footprint. It means that the hole drilled on the pad is very small. But, if it is a very large hole, the component becomes loose. It happens when the chosen components are too generic. There may be some issues with the dimension of the footprint.

You can also find issues while attaching the pin to the pad with the soldering process. A very narrow annular ring will prevent the solder from adhering to the pad. Too much heat will cause separation of the PCB base from the pad.

Another common problem is the crack in the ground pin. There is a faster dissipation of heat before the formation of the secure solder.

However, you will be able to learn through-hole soldering with repeated pitfalls.

Best practices and good equipment are essential for the PTH Soldering of a PCB. The part you want to solder needs a proper placement. When you create the circuit board, there should be enough space between parts. It will help you insert your fingers and manual soldering tools. 

So, these are some tips for creating PCBs with the PTH soldering process. Trained experts know how to optimize the PCB design with this process.