Elenco Practical Soldering Project Kit - Manual (Page 8)

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Hairline Cracks
The hairline cracks can develop in the copper foil if
the PC board is flexed. This can be easily repaired
by making a solder bridge across the two foils. The
solder should smoothly flow across the foil as shown
in Figure 8. If the solder does not adhere to the foil,
it will sit on the foil as a blob as shown in Figure 9.
1. Make five solder bridges using the second row of
single pads, starting from the left side (see Figure 10).
Reinforcing a Repair
A solder bridge repair can be reinforced using a solid
wire. Now add a wire to the five solder bridges you
just made.
1. Strip a 1/2" of insulation off one end of the wire
and then tin it.
2. Hold the tinned wire on top of the solder bridge.
3. Place the iron on the wire until the solder melts.
4. Remove the iron while holding the wire in place
against the foil. Make sure the wire does not
move until the solder hardens.
5. Check for a good solder connection.
6. Cut the wire off as close to the solder joint as
possible.
7. Practice this procedure four more times.
Wide Gaps
For wider gaps in a copper foil, a solder bridge can
not be used. A small wire would be used to bridge
the copper as shown in Figure 11. Six bridges will be
made across the two rows of small pads.
1. Place the iron on the top half of pad and then
apply the solder. Allow the solder to flow around
the pad. Then, remove the solder and the iron
and let the solder cool. The solder should be neat
and smooth.
2. Repeat Step 1 on the lower pad.
3. Strip 1/2" of insulation off one end of the wire and
then tin it.
4. Hold the wire on the top pad and then place the
iron on the wire. The solder will melt and the wire
will press down against the pad (see Figure 11).
Remove the iron while holding the wire in place
against the foil. Make sure the wire does not
move until the solder hardens.
5. Check for a good solder connection.
6. Solder the wire to the lower pad.
7. Cut the wire off as close to the solder joint as
possible (see Figure 11).
8. You can hold the wire down with a screwdriver
and resolder the wire.
9. Practice this procedure four more times on
remaining pads.
Figure 8 Figure 9
Solder
Foil
Figure 11
Solder
Foil
Bare Wire Board
Figure 10
Solder
Bridges
PC BOARD REPAIR