TM 11-5820-922-40-1
WARNING
3. Using epoxy compound, empty the
glass vial of catalyst and the syringe
of Epon into the aluminum cup and mix to
Handling hot items presents a
a complete homogeneous condition.
serious injury potential.
Asbestos gloves are required.
NOTE
The pot life of the epoxy mix-
3.
Cure the coating in an oven set at
165 F for 1-1/2 hours or by letting the
ture is approximately 30 min-
coating stand at room temperature for
utes. All material not used
within 30 minutes must be
24 hours.
discarded.
REPAIR OF DAMAGED FIBER GLASS
4.
Immediately apply the epoxy mix-
EPOXY PARTS. Damaged fiber glass parts
ture to the damaged area making sure to
may be repaired by performing the fol-
thoroughly wet the area to be repaired.
lowing steps.
5.
Apply sufficient material to cover
the entire area to be repaired. Add a
NOTE
small "crown" of material to allow for
shrinkage.
For parts other than circuit
boards, no more than 10 per-
WARNING
cent of the surface area shall
be repaired.
Handling hot items presents a
serious injury potential.
Asbestos gloves are required.
NOTE
6.
Allow the repaired area to air
For circuit boards, the area
cure for 16 hours minimum or heat cure
to be repaired shall not
in an oven for 1 hour at 150 10 F.
exceed 1 square inch; the
maximum depth of repair shall
7.
Sand or scrape the crown of the
not exceed 50 percent of the
repair until the repair is relatively
original laminate thickness;
smooth and even with the original
misdrilled holes which do not
laminate.
interfere with the function of
the circuit board shall remain
MODIFICATION OF SOLDER-PLATED
unrepaired; and minor cracks
PRINTED WIRING CIRCUIT CARDS. Solder-
which do not go through the
plated printed wiring circuit cards may
entire thickness of the
be modified by brazing gold-plated
laminate may be repaired
copper wire to solder-plated copper
according to the following
conductors. The procedural steps are as
procedure.
follows.
1.
Sand or scrape the area to be
NOTE
repaired using 80 to 180 grit sandpaper
or a scraper to remove all traces of
No more than two modification
jumper wires are allowed to be
burned or charred laminates. In the
case of a minor crack, scrape to the
brazed on one printed wiring
pad. Joints are not allowed
entire depth of the crack.
on printed circuit conductors
2.
Wipe the surface at least twice
that are less than the width
of the coined (flattened)
with a clean cloth wet with acetone and
jumper wire end.
allow to dry thoroughly.
