Removing surface-mounted ICs

From: Richard Erlacher <richard_at_idcomm.com>
Date: Mon Jun 5 10:19:08 2000

The thing I've noticed over the past few years is that there are more and
more really small parts that could be of use once you've relegated your
subject board to the rubbish heap. Space is always a problem in small
circuits and I've dealt with that to large extent by using the small
components that are on many of today's dense boards. Keeping them from
getting too hot is fairly important, though I've had pretty good yields.

Once I've determined I'll sacrifice a board for its components, I put a
cookie sheet with about 3.8" of water in it on the table on my patio. Then,
I start by heating the back side of any through-hole components I want to
salvage, often using a tool to remove them from the board. Then, I go after
the front-side surface-mounted parts, not heating them directly, but heating
the space between them, i.e. heating the pads where they're soldered to the
board. Once those are thoroughly heated, (usually with light charring and
blistering in the case of multilayered boards) I rap the board's component
side against the edge of the table, causing the loose components to fall
into the water in the cookie sheet. I don't know how well this works for
cooling the larger parts, but I've had pretty good luck all around. I find
it much more difficult to find out the values of the passives that end up in
the cookie sheet, which are pretty handy for sticking a "fix" on the back of
an IC, but it surely doesn't hurt them, and it keeps them from bouncing all
over the place.

After I'm done, there are very few bent pins and all I have to do is pour
the water through a sieve to get the teensy little passives, SOT's etc.
Then I can spend endless hours picking out these SO parts and trying to
figure out what's what. It's not much fun, but it beats watching TV.

Dick

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Received on Mon Jun 05 2000 - 10:19:08 BST