Recapping - Capacitor Removal



Important Notice


With some soldering experience you should be able to complete recapping. However, please note we TAKE NO RESPONSIBILITY for any damage to your board or device. The information we provide to assist with recapping has no warranties or guarantees. It may be incomplete, obsolete, or incorrect. Proceed at your own risk, or engage with a professional recapping service.


Removal Introduction


The capacitor removal is undoubtedly the most difficult and tedious part of this process. Especially if your PCB is comprised of 6-layers, with very tiny solder pads and holes. The problem that a 6-layer PCB presents is the fact that there is a very small tube through the entire thickness of the PCB that the components' lead solders to. This ensures the component is making solid contact with the foil traces in necessary layer of the board. The entire hole is filled with solder, not just the visible surfaces. The solder needs to be removed without removing or damaging the tube or the foil around it. If the tube or foil are damaged, it could destroy your board! Removing the actual component in itself is relatively simple. Clearing the hole of the remaining solder in order to install the new component is what can be difficult. If you have the proper tools and a little experience, you will be able to do this without damaging or destroying your board.


Capacitor Removal


This is where a stainless steel needle pick comes in really handy. A dentist pick would be ideal for this. To remove the capacitors, follow these steps:

  • - Preheat your soldering iron to roughly 400 degrees Celsius. Connect the grounding strap. For motherboards connect the strap to the metal shroud around the keyboard or USB ports.
  • - Choose your first target capacitor, and heat the POSITIVE lead up until the solder melts. If the solder won't melt, flow in some fresh solder. This will help melt it, especially if the factory solder is RoHS lead-free. With the iron still on the POSITIVE lead, push the capacitor toward the NEGATIVE lead until the POSITIVE lead is free of the board, and remove the iron.
  • - Now do the same to the NEGATIVE lead, and the capacitor will be free from the board.
  • - Now to clean the holes out... reheat the hole on the back side of the board, if necessary, melt a little fresh solder into the hole to smooth it. Then using your "solder sucker" on the front side of the hole, suck the solder from the hole. When you are done, the hole should be nice, round, and you should be able to see light through it when held up.
  • - If the hole remains closed, here's what you need to do. DO NOT TRY THE "SOLDER SUCKER" MORE THAN TWICE! If you do, you can damage your board. You need to reheat the hole until the solder is melted, then insert the needle pick into the hole as far as it will fit without forcing it, going all the way through, emerging from the other side... remove the iron and let the solder harden. Since the pick is stainless steel, the solder will not adhere to it. GENTLY spin and wiggle the pick around until it breaks loose, then remove it from the hole. Use your Exact-o knife and gently scrape the dry solder from the hole. And VIOLA!! You will have a clean open hole, ready to place a NEW capacitor in!

Remove ALL the bad capacitors before starting the installation of the new ones. This is important later on in the project, just to make sure that the same number of replacement capacitors go back into the board as came out. Trust us, on a board with a lot of capacitors, it's easy to overlook even the smallest of details. It is useful to photograph each phase of the recapping process.



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