IMHO, and
essential tool if you are serious about doing any kind of
rework is a good desoldering station. Takes a bit of time, but if done
it right, the chip just lifts out with no damage to it or the board. One
of the best investments to my workbench that I ever made....
This only seems to work on "nominal" boards -- 4 layers or
less, respectable annular rings, appropriate thermal reliefs,
etc.
Get a board with fine line rules and lots of thermal mass
on a pin (e.g., an internal power plane that is not
relieved) and you'll stand a good chance of lifting pads,
regardless.
Agreed, and even on the "normal" stuff, you still hit pins
soldered into large planes etc., so you have to have to
be careful. Even so, a very large percentage of the
material that I work on responds well to the desoldering
station ... It's one of those tools that you can get by with
without most of the time, but when you need it it really
comes in handy.
Quite often I am removing hard-to-find components from
junk boards in order to repair a different piece of equipment,
and the station leaves both in better shape than my previous
method which involved a torch.
And no (a response to another post), I didn't say it was THE
best investment I have made in my workbench - just one of
the best ones. I would put a good fine-tip soldering iron, good
storage scope, good mutimeter ahead of it ... After all I went
years without it, but I rank it quite "up there" with the other
staples now...
Dave
--
dave06a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools:
www.dunfield.com
com Collector of vintage computing equipment:
http://www.classiccmp.org/dunfield/index.html