Soldering Guru's UPDATE!!!!!?

Question

Okay I spoke with a college and he said that I would have to remove the chip and completely replace the trace that runs underneath the chip. In my case I severed the traces at the chips legs so the connection under the chip isn't powering...my question is how the heck do i remove that chip with a soldering iron...i have braid....thanks guys....

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Answer 1

Maybe heat up some piece of metal that is the size of one side of the chip melting all the leads at once then lift it up ? :)

Answer 2

The "braid" is also called solder wick.  You heat it up on top of the solder.  The solder melts and flows into the braid.

Answer 3

I don't believe you will have much luck directly with desoldering braid. Here's a few approaches you might try. If the chip is inexpensive and obtainable the easy way is to cut the chip leads close to the chip body and heat the pads one by one while pulling on the appropriate pin. Once they are all removed the desoldering braid will clear the solder from the holes or pads if it's a SMD. If you need to reuse the chip you can try one of these suggestions. One trick I have used is to add solder until I bridge all the pins on one side together. Then while prying upward with a jewelers screwdriver or better yet an IC extraction tool heat the blob quickly moving the soldering iron back and forth with the idea being to heat the solder evenly until the pins on that side let go and pull up and clear of the blob of solder. Then repeat for the other side. With DIP devices you may not get the pins clear of the blob on the first try so just pull one side out as far as practical, then do the other side, alternating sides until it's free. Then holding the board upside down heat the solder blob and let it flow to the tip and off the board. Then clean the pads with desoldering braid as before. You should practice on a similar IC on a junk PCB before making the attempt. On devices with pins on 4 sides this idea won't work. Then you will want to aquire a desoldering vacuum pump, a tool commonly known as a solder sucker. It's like a spring loaded syringe and you push in the plunger until it latches. Then you heat the pad(s) to be cleaned and while the solder is still molten place the tip of tool near the area and pull a trigger. This sends the plunger up the tube and creates a strong vacuum which sucks the pad clean. Using this method is probably the best method of the three I have suggested. One last tip is to actually add solder to the pins before using the solder sucker. I know this sound counter intuitive but it works. It adds flux which seems to help the solder melt better and flow more completely into the pump. Again use the braid for a final cleanup, clean the area with flux remover and your ready to repair that trace. I agree with the suggestion you got on one of your other questions about using wire wrap wire to repair the trace. Now clean up and straighten the pins on your IC and carefully solder it in double checking orientation BEFORE removing it and BEFORE resoldering it. You don't want to go through this ordeal twice! Any way I wish you good luck and success. Email if you have questions about any of this. I'll tell you about how I salvage IC's from old circuit boards with a propane torch!