TM 1-1500-204-23-1
NOTE
Do not use reclaimed solvents when
preparing a surface for bonding.
(g)
Mix Pro-Seal sealant according to
paragraph 9-23c(4).
(h)
Apply sealant to the ceramic surface,
and press the fiberglass patch over the crack (or cracks)
to be repaired.
(i)
Apply metal clamps or weights to the
patch to apply contact pressure equal to about five
pounds per square inch.
(j)
Place pieces of 1/8 inch fiberglass of
1/4 inch plywood pads under the clamps to distribute the
clamping force.
NOTE
Do not use rigid pads, as these will
concentrate the clamping force on the
point of contact and may crack the
ceramic tile. Maintenance activities
having the necessary equipment may
use the vacuum bag method for
clamping the patch to the tile surface.
The vacuum bag process Is used for
both fabrication and repair of glass
fabric reinforced plastic sheets. The
process consists of applying pressure
by vacuum and then curing by infrared
heat lamp or oven. An autoclave Is
also used to apply heat and pressure
for curing.
(k)
Cure Pro-Seal sealant according to
paragraph 9-23c(5).
(2)
Repair and inspection of spalled or chipped
tile. Repair and inspection procedures are as follows:
(a)
Inspect for spalled or chipped tiles
(b)
Repair spalled areas or chips In the
ceramic tile, except at the tile joints that do not exceed 1
square inch, and whose depth (at any point) does not
exceed 1/10 of the thickness of the ceramic material.
NOTE
•
Do not repair armor panels where
spalled areas or chips have a
total area greater than 1 square
inch or a depth exceeding 1/10 of
the thickness of the ceramic
material.
•
Total allowable defects are 3 or
less cracks, chips, or spalls in
any 2-inch square area. Edge
chips or spalling are acceptable
without limit within the 3/4-inch
edge boundary of the tile around
the periphery of the armor panel.
(c)
Repair
spalled
areas
or
chips
occurring in the ceramic, if they do not exceed the limits
as specified, by applying Polysulfide Sealant Pro-Seal
890.
(d)
Fill the chipped or spalled areas with
sealant, smooth flush with the ceramic surface and apply
a 1/8 Inch thick fiberglass patch The fiberglass patch
should overlap the chipped or spalled areas by three (3)
inches on each side.
(e)
Bevel all edges of the fiberglass
patch 1/4 inch deep and 30 degrees from the top surface
so that the nylon spall shield will fit smoothly over the
patch.
NOTE
For ceramic having raised edges at the
joints, one side of the patch may be
cut short of the three inch overlap
requirement. If the crack extends
through a raised edge on the raised
edge. When patching along a panel
edge, cut patch to fit the edge
boundary along periphery of the tile.
(f)
Remove existing sealant residue from
the tile surface by using a solution of 50 percent by
volume of Petroleum Distillate Base, TT-T-291 and
Toluol, TT-T-548.
(g)
Lightly abrade the fiberglass patch,
the ceramic surface surrounding the spalled or chipped
area where the patch (or patches) are to be bonded, and
the inside surface of the chipped or spalled area.
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