Make Electronics

Getting Somewhat More Serious 105

Experiment 12: Joining Two Wires Together

Now follow these steps (shown in Figures 3-32 through 3-36):

1. Make sure the tip of the soldering iron is clean (wipe it on the moist-
   ened sponge in the base of your helping hand if necessary), then touch
   it against the intersection of the wires steadily for three seconds to heat
   them. If you have hard tap water, use distilled water to wet the sponge to
   avoid a buildup of mineral deposits on the tip of your soldering iron.


2. While maintaining the iron in this position, feed a little solder onto the in-
   tersection of the wires, also touching the tip of the soldering iron. Thus, the
   two wires, the solder, and the tip of the iron should all come together at one
   point. The solder should spread over the wires within another two seconds.


3. Remove the iron and the solder. Blow on the joint to cool it. Within 10
   seconds, it should be cool enough to touch.


4. Unclamp the wires and try to tug them apart. Tug hard! If they defeat
   your best attempts to separate them, the wires are electrically joined and
   should stay joined. If you didn’t make a good joint, you will be able to
   separate the wires relatively easily, probably because you didn’t apply
   enough heat or enough solder to connect them.

The reason I asked you to begin by using the higher-powered soldering iron is
that it delivers more heat, which makes it easier to use.

Figure 3-32 Figure 3-33 Figure 3-34

Figure 3-35. This and the preceding three

figures illustrate four steps to making a

solder joint: apply heat to the wires, bring

in the solder while maintaining the heat,

wait for the solder to start to melt, and

wait a moment longer for it to form a com-

pletely molten bead. The whole process

should take between 4 and 6 seconds.

Figure 3-36. The completed joint should be

shiny, uniform, and rounded in shape.

Figure 3-31. A helping hand work aid is

shown here holding two wires with their

stripped ends touching. The magnifying

glass has been hinged out of the way.