Desoldering Chips, was Re: Can someone, > confirm this chip equivalence?

[Chuck Guzis]

On 8 Apr 2010 at 9:00, Diane Bruce wrote:

> That can cut your via. Safer to use a sewing machine needle or pin.
> Heat the solder until it is molten, clean with needle/pin as the
> solder tends not to stick to the steel. In a pinch, the end of a
> capacitor/resistor lead will do if you are careful. 

If you can--often, the problematic pin is in a via between two large 
lands and it's simply not possible to apply sufficient heat without 
damaging things.  I do have a sharpened stainless-steel pick that 
will sometimes work (solder won't stick to stainless), but sometimes 
you just have to drill.    Using a needle or a component lead in this 
case merely conducts more heat away from the area.

Another approach is to use Wood's metal (e.g. Chip-Quick) to lower 
the melting point of the solder.  I use that on SMT boards quite a 
bit with excellent results, but it also works for through-hole 
boards. Yes, it contains heavy metals which can be toxic, but it's in 
metallic form (remember all of the shiny cad-plated hardware of a few 
decades ago?).

--Chuck