4 Apr
2011
4 Apr
'11
6:32 p.m.
On 4 Apr 2011 at 18:01, Geoffrey Reed wrote:
Something you may want to consider if the desoldering
isn't going well
for you, there are a few low temp alloys made for desoldering, you
resolder the pins with the alloy and then can generally completely
clean it out using braid or a desolder tool.
Although there are commercial kits for it, when I have to remove a
many-leaded SMT chip, I'll pack a powder made from Wood's metal
around the leads and heat the underside of the PCB with a PAR-38
spotlight. Somewhere around 180-190F, the solder will let go and the
chip will slide right off. I clean up with a toothbrush, re-tin the
PCB pads and solder on the replacement.
Yes, Wood's metal has cadmium and lead in it, but the amount that's
used for a typical job is miniscule.
--Chuck