SeaPerch Remotely Operated Vehicle, Construction Manual, Page: 53 / 110

SeaPerch ROV Construction Manual
– Version 2010-04NW
2.5-1
Tips on Soldering – Safety and Techniques
Soldering Safety Reminders:
Eye Protection: Always wear safety glasses or goggles when soldering or near someone who is soldering.
Solder Hazards: Some solder contains lead, which is poisonous. Never put it in your mouth, and wash your
hands after working with it . Solder also contains a chemical flux to aid the soldering process. This causes
smoke when soldering. Avoid breathing the fumes.
Don’t Get Burned:
Soldering irons are obviously hot, so care must be taken when handling them. However,
care must also be taken when not handling them. Make sure that the hot soldering iron is placed securely in a
holder or stand when not in use so that it cannot burn you, its own cord, or anything or anyone else in the work
area. Always allow the soldering iron to cool completely before maintaining or changing the tip, or returning it to
its storage location.
Soldering Technique Tips
:
If you have not soldered before, ask your teacher to show you how, and practice on some pieces of scrap wire.
Working With Stranded Wire and Small Terminals: For best results when using stranded wire, always twist
the many wire strands together immediately
after you strip off the insulation, so that they don’t fray and break off
(or touch another connection). Then poke the wire through the hole in the terminal on a motor or a switch, twist
it back around the terminal, and squeeze it with needle-nose pliers to make a good mechanical connection . It is
important to have a solid connection before soldering, both for good heat transfer throughout the connection
while soldering and to create a strong solder joint.
Care for Soldering Irons: Always clean the heated soldering iron tip (by briefly wiping it on a moist sponge
pad)
immediately before (and after) soldering, and “re-tin” the tip with a little fresh solder just before moving to
the connection to be soldered. After soldering, always quickly clean (wipe on the damp sponge) and re-tin
(apply some fresh solder) the soldering iron tip. This is essential to keep the tip in good shape for soldering the
next connection.
Soldering: Besides protecting the tip from oxidation, applying a little solder to the tip of the soldering iron helps
to transfer heat to the junction being soldered. Apply heat with the side of the soldering iron tip (not the point,
which has very small surface area, so it can’t conduct much heat) for a few seconds to get the connection up to
solder-melting temperature. Be careful not to get it so hot that you melt any surrounding plastic, or the wire
insulation
. (Overheating a small toggle switch can actually melt some of its internal components, causing it to
fail!
– So try to work quickly on each terminal, but wait 30 seconds or so before soldering another terminal.)
Once the parts are up to temperature, melt some solder onto the connection; not just onto the soldering iron tip.
As the solder melts, it should flow into the connection. You will usually need to feed about a centimeter of thin
solder into a typical connection
(don’t use too much and make the solder joint too big!). After just a second or
so, it should flow freely in between the wire strands and over the terminal when the terminal is hot enough.
Immediately remove the solder, but hold the soldering iron on the connection for just a second or so longer to
make sure that all solder has attained its full melting temperature, and then remove the soldering iron. Try not to
move the connection at all until the solder cools and hardens (this takes just a few seconds). If you move the
wire before the solder has cooled, the solder will tend to crystallize and make a poor electrical connection.
Keeping Solder Tangle-Free: Although solder frequently comes on a large spool, it is often provided as a
smaller coil, either in a box or a tube: If your solder comes as a small coil, be sure to keep it inside the
container, only pulling out a few inches of solder at a time as it is needed. This will keep the coil from getting
tangled and becoming very difficult to use. It is a good practice to secure the top of a plastic tube of solder using
a small piece of electrical tape, so that the solder coil cannot accidentally fall out and get tangled. If you are
issued just a short length of solder at a time, such as from a large spool, coil it around a pen or pencil to help
keep it from getting lost or tangled.