CHAPTER 21 ■ SOLDERING EQUIPMENTDesoldering Vacuum Tools
Sometimes you’ll apply too much solder to a joint. The solder blob has either spread to another wire or
circuit, or is perilously close to doing so. Sometimes you’ll discover a part is wired backwards.
For whatever reason, there are times that some solder needs to be removed. Desoldering pumps and
desoldering bulbs are tools designed to suck up molten solder (see Figure 21-9).
- Squeeze the desoldering bulb or push in the desoldering pump’s spring.
- With the soldering iron, heat the solder that is currently on the joint.
- With the soldering iron still heating the joint, place the nozzle of the bulb or
pump into the molten solder. - Release the pressure on the bulb or push the pump button to cause the molten
solder to be drawn by suction into the desoldering tool. - Repeat steps 1 through 4 as necessary until the desired amount of solder is
removed. Note that it may not be possible to remove every bit of solder, but
you can usually remove enough so that the part can be pulled free when the
remaining solder is molten.
Sometimes it actually helps to add some fresh solder to a joint before attempting to remove it. If the
solder at the joint still won’t remelt, try adding some flux.
Over time, the desoldering tool’s nozzle may clog and need cleaning. At some point, it may become
worn enough to merit replacement.
Table 21-4 lists suppliers of desoldering bulbs. The desoldering pumps are fine, but I find bulbs less
cumbersome to operate with one hand.
Figure 21-9. Desoldering pump (top) and desoldering bulb (bottom) remove unwanted or excessive solder
through vacuum suction
Table 21-4. Suppliers of Desoldering Bulbs
Supplier Part Number Price
Electronix Express 060825 $2.35
Mouser 578-7805 $15.70