Elenco Solder Practice Kit w/ Iron &amp - Manual (Page 6)

Soldering Project Procedure
Before we begin to assemble and solder components to the solder
practice board, we will practice large pads on the edge of the PC board,
see Figure 2. Soldering should be smooth and neat. Next, solder to the
smaller pads. Be sure that there is no solder bridging. Try intentionally to
make a solder bridge. Then, remove it by lifting the PC board over the
soldering iron and the iron will draw the solder away from the pads. It is
best to wipe the iron tip with a damp cloth to remove the solder. Finally,
you will note the large rectangle pads. These are used to practice “tack
soldering”. Strip the end of the wire and practice soldering the wire to the
pads. Remove the wire when finished.
The PC board is covered with solder resist over areas that are not to be
soldered. This is done to reduce soldering shorts to adjacent metal runs.
On the large pad, note that half of the pad is covered with solder resist.
Try soldering the wire to the covered pad. You will find that it is impossible
to solder.
Refer to Figure 3 and begin the PC board assembly with resistor R9. Be
sure to identify the correct value by reading the color code (brown-black-
orange-gold). Place the resistor into the PC board with the leads coming
out on the copper foil side. Solder in place and clip off the excess wire
close to the connection. Proceed clockwise with the other components.
Check off the box when you have completed that step.
E. Apply a small amount of solder to the iron
tip. This allows the heat to leave the iron
and flow into the foil. Immediately apply
solder to the opposite side of the
connection, away from the iron. Allow the
heated component and circuit foil to melt
the solder.
F. Allow the solder to flow around the
connection. Then, remove the solder and
iron and let the connection cool.
The
solder should flow uniformly and not lump
around the wire. The connection should be
bright, shiny and smooth.
G. Poor solder connections occur when the
lead is not heated sufficiently. This is
called a “cold” solder joint. The solder will
not adhere to the lead as shown.
To
correct this, reheat the connection and if
necessary, apply a small amount of
additional solder to obtain a good
connection.
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H. When the foil is not heated sufficiently, the
solder will blob on the circuit board. To
correct this, reheat the connection and if
necessary, apply a small amount of
additional solder to obtain a good
connection.
I. A solder bridge may form if you accidentally
touch an adjacent foil, particularly a
previously soldered connection, use too
much solder, or drag the soldering iron
across adjacent foils.
Remove any solder
bridges with your soldering iron.
J. Do not allow components to move when
solder is cooling.
It may not solder
properly and result in a cold solder joint.
Components should be placed as close to
the board as possible. Bend the leads to
hold the part in place while soldering.
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Figure 2 Practice Solder Area
Rosin
Soldering iron
positioned incorrectly.
Tack Solder
Pad
Small Pads
Large Pads
Solder
Soldering Iron
Foil
Solder Soldering Iron
Foil
Poor solder
connection
Soldering iron positioned
incorrectly.