Solder aid is an extremely useful device which sucks the poisonous gas due to melted soldering alloy and sucks it away using an ordinary 12VDC fan removed from a computer. The circuit is shown in Fig 1. It is basically a 1.25-14.5VDC regulated voltage source built around LM317 IC.
A super bright white LED is also attached to the fan as shown in Fig. 2 to illuminate the soldering area. By 4beowulf7 - email@example.com