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I found an interesting YouTube video with a neat de-soldering trick that requires no special equipment.

Snapshot of YouTube video

Essentially you bend a reasonably thick piece of copper wire round into a right-angled S shape, add a layer of solder over the bottom edges, then place it over the chip. By heating the copper from the top, it melts the solder and provides a near perfect coverage of the IC's pins. From there you can just lift it off the board with tweezers.

Is this likely to work without damaging the IC or the board's pads, as described in the video?

Polynomial
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    If you don't need the IC, just use a craft knife and cut the pins off at the body. The pins are very easy to remove individually. If you do need the part, then I usually solder all the legs together on one side and when that blob is melted, I lift the side of the part and use my solder sucker to get rid of most of the solder. That doesn't work so well for four-sided parts. :-) – akohlsmith Dec 18 '12 at 14:24
  • @AndrewKohlsmith Cutting the pins, I never heard of anyone doing that, but I guess it would work. However with the second option, you run the risk of overheating and damaging the part. It's fairly messy too. – Garrett Fogerlie Dec 18 '12 at 14:44
  • Cutting the pins is very fast and easy. While yes I guess it's a potential problem, I've never damaged a part I've removed using the second method. – akohlsmith Dec 18 '12 at 19:49

3 Answers3

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It can work, it's not as easy as it makes it seem. You can have issues with the copper wire getting stuck to a pin here and there, or not being able to get the wire hot enough to actually melt the solder, since it takes a lot of heat. Probably not enough to damage the chip unless you leave it there for too long. I wouldn't recommend using this method. Also, this method would probably leave the PCB's pads and the chips pins messy, so you would still need to clean them.

A much easier/better/safer method to remove surface mount ICs is to take a very thin wire (like magnet wire) and thread it under all the pins on one side, then pull the wire while briefly touching the pin with a soldering iron. Essentially you're pulling the wire between the pin and the PCB's pad, and just a bit of heat allows the wire to push the pin up and separate it from the solder. Quick easy and harmless!

enter image description here

It helps if you have one side of the wire stuck or tied to something, that way you only need to pull on one side (it's a bit easier since one hand is using the soldering iron.)

Garrett Fogerlie
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  • Liking the idea of that alternative. – Polynomial Dec 18 '12 at 11:35
  • @Polynomial Yah, you'll be amazed at how easy it is. I can remove a chip faster this way then by using hot air. It helps if you have one side of the wire tied to something that way you only need to pull on one side (it's a bit easier since one had is using the soldering iron.) – Garrett Fogerlie Dec 18 '12 at 13:11
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    Sometimes (particulary when de/soldering), you would wish you were a Hindu god. ;-) – shimofuri Dec 19 '12 at 17:53
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    Genius method! +1 – abdullah kahraman Dec 22 '12 at 22:14
  • I have used this method a lot. I use thin enamelled (not self-fluxing of course) copper wire, so the solder does not stick to the wire, and the thickness of the wire lifts the lead off the pad just enough so that the joint does not form again. Take care to make sure the IC cannot move, especially as the last few leads are cleared -- the wire can pull it round and badly distort the pins. Works like a charm every time. – Harry Weston Dec 25 '12 at 19:23
  • @HarryWeston I use the same wire. I've never had an issue with twisting/breaking one of the last pins but I can see how you could. Thanks – Garrett Fogerlie Dec 25 '12 at 23:49
  • sir , did anybody tried this method and is this worked? – Standard Sandun Mar 14 '13 at 00:26
  • @sandundhammika the wire under the chip method? Yes, I use it a lot, and the people I work with do too. You need to use a wire with insulation or something so that solder or the pins don't stick to it. It is by far the easiest method I've come across! – Garrett Fogerlie Mar 14 '13 at 10:33
  • +1. That's a method I hadn't heard of before, but it sounds like it should work. Still, a hot air station is much easier. This sounds like a nice thing to try for a hobbyist that doesn't have a hot air station handy. – Olin Lathrop Mar 14 '13 at 14:32
  • anyway I think some of your information is missing. I mean information like the gauge of the coil, solder which used etc. – Standard Sandun Mar 15 '13 at 13:43
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Is it likely to work? cant say for certain untill i have tried it. But as far as i know the Solder wick is made of copper and is rather easier to use.

As for Damaging the parts(mico-chips): my suggestion would be, if you are starting out, always have some spare parts and learn how to use the Solder Wick.

The picture shown above might prove to be right, the solder will stick to the copper, and the chip will also BUT then you have to figure out how to remove chip from the copper wire (even if its not stuck to the board anymore). Also check out this question/answer:

How to tell if chips overheat while soldering

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sheetansh
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    Actually copper wicks won't work too well with very small SMD components. The capillary effects can get much stronger on the solder between the component and pad then between the solder and the wick. This will leave just enough solder to maintain the joint and that solder will be very difficult to remove with wick. – AndrejaKo Dec 18 '12 at 13:40
  • I have also found that "soldering paste" helps wick on sucking the solder. – abdullah kahraman Dec 22 '12 at 22:17
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Given that it mimics some standard desoldering tools, If you are careful, I see no reason why not.

From the Hakko website:
enter image description here

Garrett Fogerlie
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  • That one is $300 and is analog. Sparkfun has a digital hot air rework station for $100 and it works great. Highly recommended. – tcrosley Dec 18 '12 at 18:11
  • @tcrosley I may get one of those just because it looks cooler than mine. They also have a super cheap one that may work for $10 https://www.sparkfun.com/products/10326 – Garrett Fogerlie Dec 18 '12 at 18:54
  • @GarrettFogerlie Thanks for the link -- I may get one of the cheap ones for doing shrink wrap at home 'cause I'm tried of borrowing my wife's hair dryer. :) – tcrosley Dec 18 '12 at 21:00
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    This is a hot-air tool. It is really not similar at all to the idea in the OP. The linked tool is in fact a nozzle that has four separate jets, one for each row of pins on a QFN. The idea behind the OP is a contact-based heat-spreader. – Connor Wolf Dec 19 '12 at 08:18
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    @tcrosley - Digital is not in any real way necessarily better then analog for most soldering tools. Also, I can pretty much guarantee that the Hakko version is going to be significantly better designed and built then the chineese knockoff sparkfun is selling. – Connor Wolf Dec 19 '12 at 08:20
  • I just found this hot air and solder iron combo for only $130US. Looks pretty nice, anybody ever used it? – Garrett Fogerlie Jan 02 '13 at 17:53