2-6. SEALING COMPOUNDS AND ADHESIVES REMOVAL, APPLICATION, CURING, AND
a. Remove cured compound by one or more
of the following methods:
(1) Cut or scrape away with knife, then
wipe with cloth and toluene.
(2) Soak in dichloromethane until bond line
swells (about 2 hours); then remove as
in (1) above.
(3) Brush or swab with dichloromethane.
Keep compound wet until bond line
swells; then remove as in (1) above.
APPLICATION (Work life is 1 hour at
67 to 87°F.)
b. Let base and hardener containers least 24
hours at 67 to 87°F.
c. Clean surfaces with cloth and freon TMS
d. Mix curing agent in its container until it
becomes a uniform paste.
Two different types of corrosion inhibitive
sealing and coating compounds are used. If
using Pro-seal 870, go to step e. If using PR-
1436-G, go to step f.
e. Pro-seal 870: mix 100 parts base to 15
parts hardener until color is uniform. Go to
f. PR-1436-G: Mix 10 parts base to 1 part
hardener until color is uniform.
g. Fold mixture and blend for 5 minutes
minimum. Do not allow air bubbles to form.
h. Use brush or small putty knife to apply
compound as follows:
(1) Class 1A application (screws tightened
immediately upon installation) -
compound applied to threads.
(2) Class 1B application (screws tightened
after alinement) - compound applied to
heads of tightened screws.
(3) Class 1C application (mating surfaces)
- apply compound to entire mating
surface of one of the two parts.
(4) Class 2 application - apply compound
over all bonding hardware. Extend
coating to cover an area 1-1/2 times
diameter of sanded area.
Remove excess uncured compound using a
cloth and acetone or toluene.
Assemblies using class 1 application may be
handled immediately after completion of
assembly. Assemblies using class 2 may be
handled when compound becomes tack-free
i. Cure compound for 30 hours at 67 to 87°F.
END OF TASK