TM 1-1500-204-23-11
Repeat steps 1 through 5 for LML
6
surface.
Reduced strength will result if the incorrect
mix ratio is used, if an excessive amount
Failure to properly cure adhesive in accor-
of air is introduced into the adhesive during
dance with the speciied cure cycle will result in
mixing, or if mixing is inadequate and may
reduced repair strength may not be detectable
result in loss of structural integrity.
by visual or nondestructive inspection. This
may result in loss of structural integrity.
Pressure must be applied to adhesive within
the pot life of the resin. For ambient temper-
(af) Bond Patches to UML and LML Sur-
atures in excess of 90 F, decrease this time
faces (see igure 7-47, View G).
by 50%. An unsatisfactory repair will result
if the resin gels before adequate pressure is
Layup vacuum bag and heat blan-
1
applied and may result in loss of structural
ket as described in paragraph 6-18.
integrity. Select and prepare a heat blanket
(if required) and all necessary vacuum bag
2
Cure UML and LML patch bond
materials prior to mixing resin.
adhesive as described in para-
graph 6-19 using the appropriate
Prepare adhesive as described in
1
cure cycle from the system speciic
technical manual.
NOTE
3
Disassemble the vacuum bag and
the heat blanket.
Use scrim cloth if required by the system
speciic technical manual.
Remove tape.
Sand adhesive
4
squeeze out lush with edge of part.
2
Apply tape to outer side of patch to
facilitate anchoring to parent skin.
(ag) NDI Patch Bonds.
3
Apply a thin layer of adhesive in
Visually inspect adhesive squeeze
1
patch bond area on UML surface of
out at patch edge as described in
part using a spatula and adhesive
comb, per paragraph 7-6. Extend
the adhesive 1/4 inch past the patch
2
Perform NDI of patch to skin and
bond periphery.
patch to iller bond areas to verify
bondline integrity.
Apply a thin layer of adhesive on
4
bond surface of patch using a spat-
(ah) If applicable, repair outer lightning mesh
ula and adhesive comb, per para-
according to paragraph 7-12 and the
system speciic technical manual.
(ai) Reinish.
Part to patch alignment must be main-
tained within 1 degree. Fabricated com-
posite patches are orientation sensitive from
DO NOT sand into laminate near patch edge
a strength standpoint. In-correct alignment
when sanding adhesive squeeze out.
of part and patch during layup will result in
reduced strength and loss of structural integrity
1
Sand the area smooth with 180 grit
may occur.
abrasive paper. Vacuum sanding
dust from repair area. Wipe with
5
Apply bond side of patch contain-
clean, dry wiping cloth to remove
ing adhesive onto part UML surface
sanding residue.
containing adhesive. Ensure patch
is aligned on part, even with the
2
Apply inish system in accordance
part dimensions (see igure 7-47,
with paragraph 7-13b or the system
View G). Anchor with tape.
speciic technical manual.
7-84
