Tips on PCB assembly

Solder Wetting

In Soldering two metals are joined together through a solder alloy. For the permanent joining of metals, this technique is one of the oldest recorded methods. Solder wetting is such a part of the process. With metal present on the component or printed circuit board (PCB), metal is present in the solder bonds. The solder becomes fluidly molten in this wetting process and to the component for an optimal solder joint, it can stick properly.

Why there is Need for Good Solder Wetting

For proper metal joining the process of good solder, wetting is necessary. Metals will not adhere properly without this process and they will not pass industry standards for acceptable use, making them defective.

On the other hand, poor solder wetting is quite visible. The solder will look grainy, dull, and porous on Printed Circuits and will show its poor reflection on the components. In a commercial setting, this solder will often be unusable which will ultimately result in wastage of time, capital, and productivity.

Causes of Poor Solder Wetting

Poor solder wetting occurs due to various issues. Common ones are-

Over-holding the solder tip- For a long period if you hold a solder tip to the components it can result in burned flux and damaged components.

Insufficient wetting- Insufficient wetting and lack of bonding can occur because of dirty circuit boards or failure to apply heat to both the pad and pin.

Oxidation on solder surfaces- If you do not cover a hot solder tip it will react with oxygen and result in improper wetting.

Tips on Preventing Poor Solder Wetting

Use of High-Activity Solder Paste

Better wetting is offered by High-activity solder pastes, particularly when a complicated surface finish is being dealt with.

Tin Tips with Solder

Oxidation is prevented by adding solder to a hot tip. Before turning off the iron always tin your tips to keep it ready and primed for proper wetting. You can even protect yourself from the hassle and investment of continually buying replacement tips.

Clean the Surfaces

If you want to remove grease or any dirt that could lead to solder wetting on Circuits Board then a quick and effective way is to clean your surfaces and components with a general solvent wipe.