How to clean PCB?

There is no denying the significance of cleanliness, and this should not be attributed to the fact that our moms lay such a strong focus on it. Then how to clean PCB board? And is this always required? 

There is no doubt that a PCB may get tainted by grease, the oxidation of its exposed metal surfaces along with effects of PCB manufacturing process. All these factors can contribute to contamination. PCB cleaning may be required for some manufacturing processes, but this does not imply that it is essential for all of them. 

Why to Clean PCB?

Before we begin soldering, let’s take a closer look at the effects that contamination can have on PCBs.

Oxidized PBC Board
Figure 1: Example of a contaminated PCB before soldering process.

It might lead to complications while soldering. Fingerprints present on PCB also include salts, which might have an impact on the soldering process if the metallization is contacted for an extended period and the environment is damp. If there is contamination, it is possible that it has spread to places that have not been in touch with the flux or its solvent.  These marks have the potential to either cause future electrical reliability issues while the board is in service or to degrade the adhesion and overall efficacy of any post-soldering protective layer. Therefore, FS Technology believes that cleaning is an important step in the PCB assembly process steps, and if you take it lightly, it may lead to PCBA failure.

PCB cleaning tools required

If you are a hobbyist or Turnkey PCB Assembly manufacturer and you looking the ways to clean a PCB then this FS Tech blog article will assist you figure out the things, you would need to start this process. Following are some tools and materials you need to prepare ahead of time before cleaning your PCB.


Brushes for cleaning PCBs
Figure 2: Brush being used to clean PCB before soldering
If you need to clean broad areas quickly, a banister brush is a great choice, but if you need to get in close for precision work, inexpensive tin brushes from the hardware store will do the trick. When cleaning your PCB, you can get into the tinier spaces by angling the bristles of a tiny brush. This will make it possible to safely force the solvent into the board’s more inaccessible crevices. Small brushes work great for getting into small spaces circuit boards. Be careful not to scratch the circuits by using a brush with stiff bristles.

Alcoholic Solvents

alcohol for pcb cleaning
Figure 3: Different alcoholic solvents used for removing moisture from PCBs
PCBs can contain moisture if not contained in a controlled environment and this can lead to start of corrosion process which, in many cases, is main cause of PCB failure. To deal with this moisture Alcoholic solvents are used. The alcohol-based solvent reacts with water to form a solution, which subsequently evaporates along with the water. Because of this, it is the most effective method for removing corrosion damage caused by moisture on PCBs and preventing further damage.

Lint-Free Towels or Microfiber Cloths

Towels for cleaning PCBs
Figure 4: Microfiber cloth being used to clean pre-soldering area of PCB

Lint-Free Towels or Microfiber Cloths can be useful tools for performing a quick wipe down after applying a pcb board cleaner solution.  They have to be lint-free or made of microfiber to reduce the likelihood of leaving dust or other particles left in your device.

Compressed Air

Compressed Air
Figure 5: Compressed Air Jet to remove debris from PCB

Compressed air offers an inconspicuous approach to free up any dust that may have been sitting on the PCBs or within the PCB via holes, and then blows it out. This step is part of the pre-soldering and cleaning procedure. Spray the air that is contained within the ventilation openings using brief bursts.

Etching Resistant Chemical

best pcb cleaner: Etching Resistant Chemical
Figure 6:Blue coloured etching resistant chemical

Process of etching is common method used to manufacture PCBs. Etching chemicals are strong Acidic or Alkaline solutions which, if not washed properly, can cause contamination on the PCBs. So, for the purpose of removing these chemicals from PCB many Anti-Etching Solvent are used depending upon the chemical used in etching process. 

Best way to clean PCB

As the best turnkey PCB assembly company in China, in order to provide high-quality service, we add cleaning work to the entire assembly and PCB manufacturing process. Below are all our PCB cleaning processes:

Steps to Clean PCB Before Soldering

  • To start, you’ll need to place the PCB in a well-lit environment so that you can see the contaminants and does not skip any spots on PCB.
  • Blast compressed air jet on the PCB to remove any macro debris that are clearly visible to eye.
  • You should begin cleaning with your alcoholic solution using the brush with the soft bristles. After applying it to all regions of the PCB, particularly the corroded portions, you should wait a few minutes before proceeding.
  • After applying cleaning solution, remove any leftover dust or moisture, use a towel made of lint-free material or microfiber and pat it gently. Take special care not to wipe it down, since doing so might result in scratches.
  • Finally, again, apply the compressor air jet to remove any leftovers.
  • When all above steps have been carried out, carefully apply etching resistant chemical and keeping in view the soldering pad areas and you are done the pre-soldering clean procedure of PCBs. 

Precautions for cleaning the PCB

Take extra care while using the brushes and towel or microfiber cloth, so that, you may not damage the PCB sensitive section including tiny wire tracks. When cleaning component footprints for printed circuit boards (PCBs), it is in everyone’s best interest to always have access to the most up-to-date datasheets and information on the components that are being used so you may not use those chemicals which can harm the component placement terminals.

That’s all there is to provide you with PCB cleanup methods. As a leading enterprise in turnkey PCB assembly in China, FS Technology keeps all the details of manufacturing in mind.With the FS Tech’s services, it is possible to save both time and money by cooperating with a partner who is skilled in Production, PCBA testing, Circuit board assembly, and Mechanical Assembly. When working with PCBA, routine responsibilities include rewriting designs and changing components as required. This is the manner that commerce is conducted in the PCBA world. 

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