Figure 4-13.--Placing shoring over a film-covered backing plate.
Keep all glass reinforcements clean and dry. They
in the kit has a relatively short working life that
depends primarily on temperature conditions.
should not be handled with dirty or greasy hands. Cut
and handle the reinforcement carefully since the cut
IMPREGNATING THE MATERIAL AND
edges of some reinforcements unravel easily if
APPLYING THE PATCH.--There are two methods
handled carelessly. Glass cloth should be used for
for preparing the reinforcement material with resin for
most general repairs, especially where strength is
applying the patch: method one, which is particularly
important. The glass mat may be used in fillets or for
desirable for use with the vertical patch; and method
thicker buildups. alone or in combination with glass
two, which is desirable for use on horizontal surfaces
cloth.
where impregnated plies can be laid in place one at a
time. In both methods, the first step is to brush a coat
PREPARING THE RESIN SYSTEM.--The
of mixed resin formulation over the area to be
resin and hardener in the repair kit has been
repaired.
for mixing. If the temperature is much above 70F,
Method One.--On a flat surface lay a piece of
bring the resin temperature down to about 70F, as
separating film larger than the largest tailored ply of
reinforcement. Center the largest ply of glass cloth on
higher temperatures will shorten the working life of
the separating film and saturate it with resin mix by
the resin. Conversely, if the temperature is low, it is
brushing or by pouring and spreading the mix with a
advisable to keep the resin indoors until used. Prior to
wooden spatula from the repair kit. Center the second
opening the containers, clean and dry them thoroughly
tailored ply over the first ply, then impregnate it with
so that no moisture or foreign matter will get into
resin. Continue this procedure, saturating each
them. NEVER mix the hardener with the resin until
successive smaller ply thoroughly, until all tailored
the preceding steps have been accomplished. The
plies of reinforcement are finished, with the smallest
amount of resin needed for the patch may be estimated
ply on top. Apportion the resin so that there is enough
from figure 4-9.
to uniformly saturate all plies. Then cover the
Be sure to mix the entire contents of the hardener
saturated reinforcement with another sheet of
container thoroughly with the resin. Once the resin
separating film and work the air bubbles out by
formulation has been thoroughly mixed, the "die is
squeezing the wet reinforcement from the center
cast." Work ahead steadily to complete the repair
outward with a clean spatula or spreader from the kit.
within the working life of the resin. The resin system
Keep a close check that the time does not exceed the
4-13