[remove soldered chips]

[Harry Bissell]

The best way is with a vaccuum desoldering station. It has a soldering iron
with a hollow tip, and a vaccuum pump that sucks the solder when you press a
button on the handle. Quite good. Quite expensive. No???

O.K. just kidding. Use Solder Wick. It is available in various sizes. Don't
use the real big stuff for ICs. The size about 1/10" wide is probably about
right. With the soldering iron tip just a liile wetted with solder, apply the
wick to the junction of the ic lead and the pad. Heat the wick with the iron,
and the solder will flow into the wick from capillary action. Do one hole at a
time. Don't overheat... if it doesn't wick clean, add a tiny bit of solder
back to the joint and try again.
Cut off the used portion of wick after each hole... you can't be cheap if you
want to save both chip and pcb...

When you are done, take needlenose pliers and very gently wiggle the IC lead
in and out (toward the center of the IC and away, not end to end...) You
should either see the lead move easily, or it may "snap" away from the plating
in the hole. If it doesn't, the solder didn't all come out of the hole. Put
more solder in the hole, heat it a little longer this time, and then use the
wick again. This happens often when there is a heavy trace on the component
side of the PCB that acts as a heatsink, preventing the solder from melting at
the top of the hole.

When all of the pins are free, slip a small screwdeiver under each end and
twist gently. Try to do it in a place where the screwdriver blade can't nick
any traces. The IC will usually just pop right out. If it sticks, look for the
pin or pins that are stuck, and use the solder wick again.

If the IC is expendable... cut the IC leads right at the plastic body of the
chip with very small and sharp cutting pliers. Then heat each hole from the
solder side while holding the stump of the pin with needlenose pliers from the
component side, when the solder melts just slide the pin right out. Clean up
the holes with solder wick.

Good Luck. :-) Harry (been there, done that, and often...) Bissell

Zsolt Homlokos <Zsolt.Homlokos at rz.ruhr-uni-bochum.de> wrote:
which is the best way to remove soldered chips?
i tried to get rid of most of the solder with a solder-sucker,but the
chip still doesnt move and i  am afraid of breaking  of the pins .
are there any tricks?
thanks
Zsolt


if this post comes twice:sorry


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