removing parts from PCBs

[Chuck Guzis]

On 11/14/2005 at 11:24 PM Jeff Walther wrote:

>For big surface mount chips I like to use Chip Quik desoldering 
>alloy, which will lower the melting point of the solder on the board. 
>If I preapply Chip Quik, I can usually use the 600F setting for a 
>minute or two to loosen a chip.  I've successfully done this on chips 
>as large as 208 pin QFPs.

Jeff, unless the thermostat on your heat gun is faulty, you should be able
to go much lower than 600F, shouldn't you?  60/40 solder flows at about
370F.

It seems to me that I've also seen special desoldering rigs that use hot
air and a special nozzle to better focus the airstream.

Thanks for the tip on Chip Quik; from the MSDS, it appears to be a
Tin-Indium alloy.

Cheers,
Chuck