How to Clean Printed Circuit Boards

Printed circuit boards that are components of commonly used devices like smartphones and tablets can be subject to a wide variety of contaminants over the course of their use. There is an increasing need for services to clean PCBs that have been corrupted by contaminants but not actually physically broken. In this article, we will outline how to clean printed circuit boards and what to use.

Challenges to Circuit Board Cleaning

Cleaning printed circuit boards is a very delicate process. When you are working with a printed circuit board, you are dealing with a variety of exposed components and connections that can easily be damaged if you attempt to clean the board improperly. How you will approach cleaning your printed circuit board will depend in large part on the types of contaminants you are dealing with.

Contaminants you may have to clean from a printed circuit board include:

How to Clean Dust or Dirt from Printed Circuit Board

These dry contaminants are the first things most people think of when they consider a PCB that needs to be cleaned. It is easy for dirt or dust to get into a printed circuit board and just as easy for that debris to render the device containing the PCB unusable. There are a number of ways to deal with this type of contamination:

  • Brushing: Very carefully and gingerly, use a small brush, like a touch-up paintbrush, to remove dirt or dust from a board without damaging components. If the dirt or dust is in an area inaccessible by even a micro-brush, refer to one of the other methods.


  • Compressed Air: Compressed air is a common method of clearing dirt and dust from electronic components. However, it is possible for this method to damage connections, so you should use it sparingly.


  • Electronic Component Vacuum: These are special vacuums some manufacture use for cleaning electronic components. Do not use an ordinary vacuum for this purpose.


How to Clean Wet Contaminants on a Printed Circuit Boards 

Wet contaminants, like soda, grime or oil, can create a sticky film on your printed circuit board that can be a real problem, both on its own and for its ability to attract additional dust and dirt. The above methods will not be effective for removing these contaminants. Fortunately, there are other methods that will, such as:

  • Isopropyl Alcohol: Using a Q-tip or similar small cotton implement, gently clean the PCB by dipping the swab in alcohol and running it over the contaminated parts of the board. Make sure you are in a well-ventilated environment, as this method can produce toxic fumes.


  • Demineralized Water: If you don’t want to use alcohol or don’t have access to it, you can use demineralized water instead. Of course, you need to minimize the amount of moisture you subject the circuit board to and make sure to thoroughly dry it before attempting to use it again.


  • Specialty Cleaning Agents: You can find PCB cleaning agents that are tailored toward specific wet contaminants at many electronics wholesalers or retailers. Stronger cleaning agents may damage plastics, remove markings or cause other issues, so be careful with the strength of the agents you choose. If you are dealing with a strong cleaning agent, you may want to test it on an old board that you aren’t afraid to damage first.


What is Ultrasonic PCB Cleaning

Ultrasonic PCB cleaning is an all-purpose cleaning method that cleans through cavitation. Essentially, this means the ultrasonic PCB cleaning machine sends high-frequency soundwaves into a tank filled with cleaning solution while your PCB is immersed in it. This causes billions of tiny bubbles inside the cleaning solution to implode, blowing any contaminants off the printed circuit board without harming the components or anything else.

Unfortunately, it is possible for this method to separate component end caps, loosen connections and otherwise damage components. However, if your board has contaminants in an area no other method can reach, this is a quick and easy way of getting those areas clean.

As you can see, there are a number of methods for effectively cleaning PCBs. If you have contaminated PCBs, see if one or more of these cleaning methods will work for you.

MCL for Clean, High-Quality Printed Circuit Boards for All Your Applications

Millennium Circuits Limited can provide you with brand-new, highly effective printed circuit boards in a variety of types and materials. To learn more about MCL printed circuit board products, or for more information on PCB cleaning and other methods of keeping printed circuit boards in top condition, contact MCL today.