It's a sad reality that no solder operation produces 100% perfect assemblies and even the highest quality components fail from time to time.
Anyone who manufacturers, maintains, or repairs electronics needs an efficient and effective way to remove excess solder. For example to eliminate bridging between contacts, or to remove solder after component has been pulled.
Solder suckers produce inconsistent results because the tool cannot maintain a good suction over molten solder. Desoldering stations are more effective but can be time consuming and the equipment requires constant maintenance to keep it working.
Desoldering braid on the other hand is an excellent way to clean unwanted solder from a circuit board because it's inexpensive, effective and eliminates the need for additional capital equipment. Solder Wick Desoldering braid is the most popular all over the world as because Solder Wick was the first desoldering braid developed over 40 years ago and meets military aerospace and industrial specifications like any technical tools there are best practices that can improve your efficiency.
Tip 1: Match the Flux type to your process:
Solder Wick desoldering braid is available in various flux types depending on your cleaning process and other requirements.
Rosin flux braid is the fastest wicking action but it does leave behind residues that need to be thoroughly cleaned with isopropyl alcohol or Chemtronics flux off brand cleaners will do an effective job.
No clean flux braid is ideal when cleaning isn't practical or possible where clear non ionic residue is left behind and is safe to be left on the board.
Lead free braid combines a proprietary no clean flux and braid design that heats up quickly so it avoids heat stress of components even at the higher lead free temperatures.
In a production or repair environment when the flux is already specified or when an aqueous flux is needed you can add your own flux to this type of braid.
Tip 2: choose static dissipative packaging for static sensitive applications
Solder wick comes in various lengths, including longer lengths like 25, 50 and 100 feet. They come in insulative plastic spools that can generate a charge.
For work around static sensitive assemblies use a static dissipative or ESD safe blue bobbin that comes standard for five foot & 10 foot lengths.
Tip 3: match braid width to the solder joint or contact pad
It's important to choose a desoldering braid that closely matches the size of the contact pad. Smaller widths won't remove enough solder and larger widths take longer to heat up and may interfere with other components on circuit board.
Widths of braid are designed by the numbers 1-6 or color codes, which are standard in the industry.
Number one braid is the smallest & most fine.
Number 2 #3 and #4 are the most commonly used
Number 5 is ideal for removing large blobs solder
Number 6 is best for Desoldering BGA pads.
Most find it helpful to keep three or four different widths in their work area
Tip 4: Match your soldering iron tip to the braid width
Choose a soldering tip with a width similar to that of the braid. You want to heat the whole break quickly but without interfering with surrounding components. Too small and you aren't able to transfer enough heat to the braid, too large and you're applying too much heat and run the risk of causing thermal stress or disordering unintended areas. A blade or knife is helpful when deciding large areas like a BGA pad.
Tip 5: Before starting, tin soldering tip with fresh solder.
A well coated soldering tip conducts heat more efficiently to the disordering braid it starts to wicking action more quickly.
Tip 6: To pick up solder in tight areas, add solder first.
Small amounts of solder in tight crevices can be difficult to remove, but larger uniform soldered joints Wick right up. As counterintuitive as it sounds it helps to add more soldered to joints like this before wicking up unwanted solder.
Tip 7: When drag desoldering, move the tip over the braid, not over the pads.
Dragging the copper braid over pads, for example when soldering BGA pads can scratch OSP coating and even the pads themselves if enough pressure is applied. It's best to apply the braid then drag the soldering tip over the braid.
Tip 8: When solder is removed lift up the iron and braid at the same time.
Always lift up the braid and soldering tip at the same time otherwise you run the risk of soldering the braid to the board. This is the number one rookie mistake and a good way to remove contact pads along with the solder.
Tip 9: Clip used braid after each use.
It's best to work on the end of the braid to isolate the heat. That leaves less copper to heat and reduces the risk of using a part of the braid where the flux is already been activated.
Tip 10: Clean flux residues with the quality flux remover.
Finally after all the components in excess solder have been removed clean the area thoroughly with a quality flux remover like Chemtronics flux off cleaners. This is an optional step for no clean and lead free braid, but still a good idea for densely populated or high voltage boards remember to angle the board to allow the cleaner and residues to run off.
So with these steps you are using the industry tested best practices to remove unwanted solder from a circuit board Solder Wick desoldering braid is an effective and cost effective tool for any electronic rework and repair operation whether you run a multi-National Assembly operation or have a backroom repair shop.
