CIRCUIT CARD ASSEMBLY REPAIR PROCEDURES
3-10. Excessive Solder. Solder that
flows beyond the bend radius of a com-
3-4. This section contains description
ponent lead is not acceptable, except
and definitions of standards to be
for small diameter components (for
observed followed by procedures to be
example, glass diodes). The maximum
performed for repair of circuit cards
solder height, including component lead,
and replacement of components. Read the
on the bottom of the board is 0.062 inch
procedures in this section before
attempting card repair.
exceed 0.062 inch.
3-11. Insufficient Solder. Except for
permisssible voids and pinholes, the
3-6. SOLDERING STANDARDS FOR CIRCUIT
solder must fill the hole to the point
CARDS. The following paragraphs contain
where the solder covers the entire inner
surface of the hole. For eyelet holes
or standoff terminals with circuit con-
nections, the solder should flow between
the eyelet and the pad for at least four-
ifths of the circumference.
is an area which is not filled with
solder, the extent of which is com-
pletely visible. For cards with eyelets
3-12. Cold Solder Joints. Cold solder
or plated-through holes, voids in the
circuit side of a solder joint are per-
at the point of contact with a pad or
lead are not acceptable.
missible, provided that they are not
deeper than half of the hole depth and
do not extend over more than a quarter
3-13. Preferred Solder Connections.
of the hole area. If no circuit is con-
All components may be soldered by either
flow soldering or by hand soldering.
nected to the pad on the side of the
void, the void may extend over the
The completed joint must have a clear,
smooth appearance which indicates proper
entire hole area if the outline of the
lead is visible. Voids in unsupported
holes may extend through the hole but
should not extend over more than a fifth
of the hole area.
3-14. CIRCUIT CARD BASE MATERIAL
STANDARDS. Cracks, chips, or gouges in
3-8. Soldering Pinholes.
the base material should not exceed the
a hole in the surface of the solder
which indicates the absence of solder
beneath the surface, the extent of which
1. Cracks or chips should not exceed
back from the edge of the hole more than
should not be permitted adjacent to the
component lead or wire.
2. Cracks, chips, and gouges at the
3-9. Pad Area. Solder
is not required
edge of the board should not exceed 1/3
to cover the entire pad area. Voids and
of the board thickness or extend back
pinholes in these areas are acceptable.
more than 0.12 inch from the edge.