[sdiy] Desoldering techniques for chips that you want to keep?

[Scott Gravenhorst]

I'm not suggesting this at all, but I remember watching someone do it (VERY CAREFULLY)
using a propane torch with a fan tip.  He would shake the board after the solder was
melted and most of the chips just fell out.

The worst situation is where all of the leads are bent over before soldering.  So if
it's the _board_ that's valuable, I would simply cut the ICs off with diagonal cutters
and then unsolder the lead pieces.  If the _ICs_ are valuable, then you have to unsolder
them carefully.  I've had good luck with desoldering pins one at a time, but I've never
tried to harvest tens or hundreds of chips that way - I'm sure it would be tedious and
time consuming.  I can see where the "all-pins" tip could work, but only with a
correctly sized heating element.

Seb Francis <seb at burnit.co.uk> wrote:
>It's pretty hard.  If you want to be sure not to damage the PCB then you 
>are better off sacrificing the IC - cut the pins and desolder individually.
>
>But you can get special soldering iron bit that will desolder up to a 
>16pin DIP IC all in 1 go (it sits on all pins at once).  This is the 
>best way I can think of.  Maybe with a single sided board you'd be able 
>to manage by removing the solder with a solder sucker or desoldering 
>braid, but with double sided PTH boards it'll be near enough impossible 
>to do this.
>
>Seb
>
>
>steve jones wrote:
>
>>Newbie stuff.... I've always used chip sockets for my DIY projects so
>>far, so this is new to me...
>>I'm looking for info on how to desolder and remove chips from a
>>circuit board without damaging either. Should I use a solder sucker or
>>copper braid? Flux? Soldering iron size / power? Should I add new
>>solder to start with? How tough are chips anyway?
>>General advice most welcome.
>>Steve
>>
>>
>>
>>
>>  
>>
>

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