TM 10-5410-224-14
e. Replacing shelter seals. The following
sheet , where the face sheet is surrounded by
procedure is recommended for replacing any shelter
cracks.
seal.
(1) Stop-drill all cracks, using a No. 30 drill.
(1) Remove defective seal.
(2) Sand damage area with sand paper to
(2) Strip off old sealant from structure.
remove all traces of paint. Remove paint for a
distance of 1-1/4 inches all around damage.
(3) Clean bonding surface with sand paper.
CAUTION
(3) Cut a rectangular patch one inch larger all
Seals must not be washed with any
around than damage area. Make patch same
aromatic hydrocarbon (such as benzene,
thickness as a panel face sheet.
toluene, and xylene).
(4) Lay out hole pattern in patch. Use 1/4-
(4) Clean seal and bonding surface to which it
inch edge distance and 1-inch spacing. Drill holes,
is to be attached, using a clean cloth dampened
using No. 30 drill.
in acetone. Dry immediately with a clean cloth.
(5) Center patch over damaged area and drill
through face sheet, using prechilled holes in patch
(5) Mix adhesive FE 6026 Parts A and B
according to the manufacturer's instructions.
as a guide.
(6) Remove patch, and remove burrs from all
Brush on bonding surface to which seal will be
drilled holes.
attached.
(6) Within ten minutes after application of
(7) Prepare bonding surfaces of face sheet and
sealant, place seal in position and immediately
patch for bonding by sanding until oxide film is
removed.
smooth sealant.
NOTE
WARNING-[
If seal is the type that is to be riveted to
Bring no more methylethyl ketone into
aluminum retaining strip, dip rivets in sealing
area than is needed.
compound MI L-S-8802. After installation rivets,
(8) Wipe surface with a cloth soaked in
cover rivets and seal with sealing compound.
methylethyl ketone and immediately wipe solvent
(7) Clamp in place overnight, using sufficient
from surface with a clean cloth. Wear gloves to
pressure to ensure firm contact without distorting
avoid contaminating the cleaned surfaces with
shape of seal. Overnight curing will provide
dirt, oi1 or fingerprints.
holding strength; full strength will be attained
(9) Mix sufficient quantity of epoxy for the
after seven days.
repair. Place epoxy in damaged area and let cure.
f. Caulking Repaired Areas. After a repair to
(10) Apply a thin, even coat of sealing
the expandable shelter structure has been com-
compound, MIL-S-8802, to bonding surfaces of
pleted, it must be caulked to seal out water and
face sheet and patch.
moisture. Sealant, MIL-S-8802 is used for caulking
(11) Secure patch to face sheet using 1/8-inch
repaired areas and under fasteners. This is a two-
sheet fasteners.
part material consisting of a Thiokol base and an
(12) Dip rivets in sealing compound, MIL-S-
accelerator. Nominal pot life of this compound is 8
8802.
hours; nominal curing time is 140 hours. The
(13) Install 1/8-inch universal head blind
following general procedure is recommended for
rivets in all drilled holes.
mixing and applying the compounds.
(14) After installation cover rivets with sealing
NOTE
Caulking under/around fasteners (rivets, screws,
compounds.
bolts, etc.) is also a requirement at their in-
(15) Remove any excess epoxy from outer
stallation.
surfaces of repair.
The sealant is furnished in kit form and may be
(16) After the repair has cured, caulk edges of
mixed in the can containing the Thiokol. Mixing
patch in accordance with paragraph 3-16f. and
ratio is as specified on the can by the manufac-
turer.
paint repaired surfaces in accordance with
(1) Stir the accelerator to a smooth, creamy
d. Repairing Both Panel Faces. The following
paste, using a spatula or putty knife.
procedure is used for repairing damage that ex-
(2) Mix the accelerator into the compound and
tends through both panel faces.
stir thoroughly until no streaks of accelerator or
(1) Clean protuding metal or damage core from
unmixed compound are visible. Mix the material
hole.
thoroughly at sides and bottom of can. Thorough
(2) If practical, fill hole with epoxy filler and
mixing requires at least 5 minutes.
rivet patch `on each face of panel.
(3) After mixing is completed, the sealant is
(3) If cut is too large to fill, make temporary
applied, using a caulking gun, spatula, hypodermic
repair by installing double patch to both surfaces
syringe, or putty knife.
without the filler. Use procedures of paragraph 3-
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