DIYbanter - View Single Post - PCB track fault

Randy Day[_2_]

In article ,
says...

[snip]

As for the failed C pad
This pad had survived original soldering, my first desolder and resolder and
came away with second desoldering leaving bare board where the pad was.
I expected to see copper colour after scraping into the white circle but
only silver colour of solder seen - no copper pad there ever? so thin it
disolved ? when I desoldered/resoldered initially there was a normal pad of
solder there

Most likely the pad came away with the soldering
iron tip on the last reflow. It's probably
sitting on your tip cleaning sponge with all the
flux residue, or in your vacuum desoldering tool.
It's very easy to do and easy to miss.

Anytime you reflow a pad more than once, you have
an increased likelihood that this will happen.
The copper adhesive isn't intended to be melted
over and over...