TM 55-8145-202-14
a.
Repair: Mid-Panel Patch Overlay.
(1) Flatten the panel surface to remove distortion, wrinkles and creases. If necessary, cut away damage
until the surface is flat, leaving a smooth hole with even edges.
(2) Check foam insulation for moisture and damage. If foam is damaged, cut out damaged portion notify
Direct Support Maintenance.
(3) Prepare a rectangular patch with rounded corners to overlap the damaged area by 2 inches (50 mm) on
all sides. The patch material must be of the same specification as the damaged panel, and pre-
painted if the damaged panel is painted. Clean and sand the portion of panel to be overlapped.
(4) If the patch is to be fitted over rivets securing a side post in place, remove the rivets to be covered by
the patch. Measure the diameter of the holes and the distance (pitch) between rivets.
(5) Center patch over damage and drill four holes, one in each corner of the patch, 1/2 inch (13 mm) from
the edge. To reduce damage to the foam insulation, use a stop on the drill bit to limit depth of drill to
3/4 inch (20 mm).
(6) Secure the patch with clips or clamps and drill remaining holes around the border of the patch.
Holes should be on 1 inch (25 mm) centers, 1/2 inch (13 mm) from the edge.
(7) Remove the patch. De-burr the holes. Apply foam adhesive primer to the inside of the patch.
(8) Apply a continuous bead of sealant to the patch between the line of rivet holes and the edge; OR use
adhesive tape around the inner perimeter of the patch. The tape must be mitered or overlap at the
corners of the patch. Tape should be measured to reach all edges of the patch.
(9) Position patch, align holes and smooth patch to expel excess sealant. Rivet patch using appropriate
rivets meeting requirements in the corners of the patch, and blind fasteners around the rest. On larger
patches, it may be necessary to support the patch with a piece of wood, pressing firmly until the
adhesive is cured.
(10) If tape was used, trim any excess. Be careful not to score paint. Replace decals if damaged. If drive
rivets were used, coat with sealant.
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