Hints for desoldering
DISCLAIMER: I take no responsiblity for you screwing anything up from following these instructions. Desoldering a chip is a very tricky procedure. I've done it a lot and still mess up. Hints are no substitute for practice and experience!
First of all, know what your goal is. Is your goal to remove an unwanted
chip from an important board, or to remove an important chip from an unwanted
If it's the former, the best way is to cut off all the legs of the chip, then
desolder each pin individually. The pins can then be removed with a soldering
iron and a pair of pilers. Cleaning out the holes with a desoldering iron is
rather simple at that point.
But if it's the chip you want, here's some tips for desoldering DIP package
- I use a Radio Shack desoldering iron. This has a red rubber bulb on it
and a hollow tip. It's cheap and works well.
- Use a fresh tip for important projects! It's not worth trying to save
two bucks only to ruin a circuit board or a chip.
- New tips must be tinned! If not tinned, their lifetime is only
a few hours.
- Practice, pratice, practice! It will help to practice on a junk board
rather than messing up on your first attempt with an important chip.
- The higher-tech the board you are desoldering from, the more difficult
it will be. Old-fashioned one- and two-layer boards are the easiest.
Newer boards tend to have smaller holes which make suction much more
- Wait for the joint to completely melt before sucking out the solder. If
you suck too soon, you may not be able to melt the joint properly any
more. Wait about four seconds, or five for the four "corner" pins.
- When you have sucked out the solder from all of the holes, push all the
pins to "crack" them off of the remaining solder in the hole.
- If you have done everything right, and it's a one- or two-layer board,
the chip should practically fall out of the board. If not, you need
to very carefully pry the chip up, just a little at a time
from each end. Watch for pins that are clearly stuck. You may need to
use a soldering iron to heat the pin while pulling.
- Any pins which have lost their bottom half need to be repaired.
Simply get a new pin from a donor IC, and solder it onto the stump.