The soldering of electronic components onto circuit boards is a very necessary step in PCB assembly. However, what if you put the wrong component, or you need to upgrade the component later? That is the time when you would need desoldering. Desoldering is a process that removes the solder and components from a printed circuit board or any other type of electronic assembly. This is a meticulous process and it can easily damage the board, or the components, if not properly done. Thus, it is important to know how to desolder properly. In this article, we will describe 6 effective desoldering methods one by one. Let us begin.
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How to Desolder with a Soldering Iron
Step 1: The soldering iron should be heated up to the temperature that the solder can melt.
Step 2: Turn on the soldering iron and place it on the solder joint and heat it up until the solder has melted.
Step 3: The tip of the iron should be gently pushed to move the component pins and thus, the solder will be taken away from the joint.
Step 4: By applying the pliers, you can pull the component out of the PCB.
Remove components NOTE: The force should be on the tips of the components, because while applying force to the main body, the damage to the components might be caused.
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Using a Desoldering Braid
To use a desoldering braid effectively, following below steps:
Step 1: Prepare the braid by dipping the end into some solder flux if it doesn’t have a flux coating already. The flux helps the solder flow and wick into the braid better.
Step 2: Using tweezers or pliers to handle the braid (since it will get very hot), position the fluxed end of the braid over the solder joint or component lead you want to desolder.
Step 3: Place the tip of your hot soldering iron onto the braid and the component lead simultaneously. As the solder melts, it will get absorbed or wicked into the braid’s braided copper wires. Keep the braid and iron in place until all the solder is removed from the joint.
Step 4: If some solder remains, reposition the braid to expose a fresh section and repeat step 3. Trim off any used, solder-saturated portions of the braid as you go to work with a clean section.
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How to Use a Desoldering Pump
A desoldering pump is a necessary tool that uses the force of suction to remove the molten solder from the circuit board hole and pads.
Step 1: Heat the solder joint you want to desolder with your soldering iron until the solder turns completely into the liquid state.
Step 2: Put the suction cup tip of the pump directly above the molten solder joint.
Step 3: The handle of the pump should be squeezed to make suction inside the tip.
Step 4: Although, you have to keep the tip of the pump pressing the joint firmly, you have to quickly release the pump handle. The molten solder will be drawn into the pump’s internal reservoir.
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Desoldering with a Power Desoldering Station
Desoldering the large-scale or the tricky tasks, a temperature-controlled desoldering station gives better control and efficiency than the manual methods. These specialized power tools are meant to be used for the desoldering of numerous components.
Common desoldering station types include:
- The through-hole desoldering stations which involve the use of suction or desoldering wicks to remove the through-hole components in a good way.
- Hot tweezer stations, essential for surface-mount work, using heated tweezers to grip and desolder SMD componentsfrom their pads.
- Hot air rework stations that use scorching 800-1000°F airflow to melt solder cleanly, facilitating safe desoldering of surface-mount parts.
As to the use of desoldering station, it’s crucial to consult the instruction manual for proper usage of the specific station type.
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How to Desolder with aSoldering Pot
A solder pot is usually employed to desolder several connections and bigger components at the same time. This tool has a heated reservoir with molten solder which, in turn, makes the solder joints easy to remove. Here’s how it works:
Step 1: Check if the pot is clean and heated to the correct temperature before you melt your solder alloy. The joints you want to desolder should be treated with some flux – this will make the solder to flow smoothly.
Step 2: By means of tweezers or a tool, carefully, put the component right into the molten solder bath. Let is stay for a few seconds until the solder joints become liquid. After that, carefully lift the component out, letting the excess solder spill back into the pot.
Step 3: Verify that all the joints are clean and solder-free. In case of necessity, use a brush or a cleaner to clean out the flux residue.
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How to Desoler with Compressed Air
Using compressed air for desoldering can be implemented in two different ways: using a soldering iron or not using a soldering iron.
Option 1: Using a Soldering Iron
Heat the Solder: Use a soldering iron to melt solder at the joints of the component you want to remove.
Apply Compressed Air: Place the nozzle of a compressed air gun near the melted solder.
Blast the Solder Away: Trigger the compressed air gun to forcefully blow the melted solder off the PCB to clear the joint.
Option 2: Without a Soldering Iron
Prepare Compressed Air Can: Turn a can of compressed air upside down to use it in a way that it sprays out freezing liquid it contains.
Spray on Solder: Direct this spray into the solder joints of the component. The extreme cold will make the solder brittle.
Remove the Component: After a few minutes, you can either gently pull out the component with pliers or, if it is firmly soldered, lightly tap the joint to break the now brittle solder and then remove the component.
