TM 1-1500-204-23-11
Fill the core cells from the bottom
3
up to prevent the formation of bub-
bles.
DO NOT sand into laminate when remov-
ing paint. When working on a carbon iber
If performing a scab repair, ill the
4
laminate, a black colored dust on the sand-
core cavity slightly above the part
paper indicates that sanding into the laminate
surface mold line. If performing
occurred and carbon iber is being removed.
a lush repair, ill the core cav-
If this occurs, the sanding process should
ity slightly above the original core
be stopped immediately. A loss of structural
mold line.
integrity may occur if ibers are exposed or
damaged.
(d) Paint Removal. Remove paint from
Failure to properly cure adhesive in accor-
skin in the repair area by sanding as
dance with the speciied cure cycle will result in
described in paragraph 6-1. Ensure to
reduced repair strength may not be detectable
vacuum the repair area and then wipe
by visual or nondestructive inspection. This
with clean wiping cloth to remove sand-
may result in loss of structural integrity.
ing dust.
NOTE
(e) If damage is through both skins, cover
the hole on the lower skin with release
Some potting compounds shrink during cure.
ilm and tape in place. Apply a metal
If using a mixture that is likely to shrink, build
plate formed to the part contour over
compound slightly above the part surface.
the ilm and tape in place on the part
surface.
Using a heat lamp or heating blan-
5
ket, cure the potting compound
according to paragraph 6-19 and
the system speciic technical man-
ual. Allow the repair area to cool.
Allow a minimum of 2 hours between 100
gram applications in the repair cavity.
(g) Machine Core Flush with OML(s). Trim
the top of the cured potting compound
(f)
Prepare and Apply Adhesive into Cavity.
lush with either the original core or the
part mold line (as shown in igure 7-13,
1
Select the appropriate potting
View D), depending on the type of repair
adhesive according to the system
being performed.
speciic technical manual.
1
Sand adhesive using an orbital
sander and 180 grit abrasive
paper. The inished surface should
Reduced strength will result if the incorrect
be left comparatively rough (not
mix ratio is used, if an excessive amount
smoothed) to improve bonding to
of air is introduced into the adhesive during
the skin.
mixing, or if mixing is inadequate and may
Vacuum the repair area to remove
2
result in loss of structural integrity.
sanding dust.
Pressure must be applied to adhesive within
the pot life of the resin. For ambient temper-
3
Wipe area with clean wiping cloth
atures in excess of 90 F, decrease this time
to remove sanding dust.
by 50%. An unsatisfactory repair will result
if the resin gels before adequate pressure is
(h) Dry Repair Area. Dry repair area as
applied and may result in loss of structural
described in paragraph 6-6 using a heat
integrity. Select and prepare a heat blanket
blanket to remove subsurface moisture.
(if required) and all necessary vacuum bag
(i)
Prepare Skin Surface for Bonding.
materials prior to mixing resin.
Lightly hand sand with 150-180 grit
Mix the potting adhesive according
abrasive paper as described in para-
2
graph 6-7. Handle prepared surfaces
7-24
