Experiment 12: Joining Two Wires Together
110 Chapter 3
Adding Insulation
After you’ve succeeded in making a good inline solder connection between
two wires, it’s time for the easy part. Choose some heat-shrink tubing that is
just big enough to slide over the joint with a little bit of room to spare.Figure 3-47. Other members of your family should understand that although a heat gun
looks like a hair dryer, appearances may be deceptive.Slide the tubing along until the joint is centered under it, hold it in front of
your heat gun, and switch on the gun (keeping your fingers away from the
blast of superheated air). Turn the wire so that you heat both sides. The tubing
should shrink tight around the joint within half a minute. If you overheat the
tubing, it may shrink so much that it splits, at which point you must remove
it and start over. As soon as the tubing is tight around the wire, your job is
done, and there’s no point in making it any hotter. Figures 3-48 through 3-50
show the desired result. I used white tubing because it shows up well in photo-
graphs. Different colors of heat-shrink tubing all perform the same way.Figure 3-48. Slip the tubing over your wire
joint.
Figure 3-49. Apply heat to the tubing. Figure 3-50. Leave the heat on the tubing
until it shrinks to firmly cover the joint.Heat Guns Get Hot, Too!
Notice the chromed steel tube at the
business end of your heat gun. Steel
costs more than plastic, so the manu-
facturer must have put it there for a
good reason—and the reason is that
the air flowing through it becomes so
hot that it would melt a plastic tube.
The metal tube stays hot enough to
burn you for several minutes after
you’ve used it. And, as in the case of
soldering irons, other people (and
pets) are vulnerable, because they
won’t necessarily know that the heat
gun is hot. Most of all, make sure that
no one in your home ever makes the
mistake of using a heat gun as a hair
dryer (Figure 3-47).
This tool is just a little more hazard-
ous than it appears.