Note. In general, trimmed holes are not restricted as to size
or shape; however, those of rectangular, circular, square and oval
and rectangular with round ends usually are more desirable as to
appearance and ease of installation.
(3) Clean the interior surface of the undamaged
facing with emery cloth, and a clean lint-free cloth
soaked with methyl ethyl ketone.
(4) Cut a plug patch plate of the same size as the
trimmed hole using the aluminum facing furnished
with the repair kit.
(5) Cut a section of honeycomb core material the
same size as the trimmed hole using the honeycomb
core furnished with the repair kit.
(6) Fabricate a doubler plate the same shape as
(7) Drill rivet holes in the doubler plate using a
number 30 drill (0.128-0.132 inch diameter) and
(8) Drill matching holes in the plug patch plate
and panel using the doubler plate as a template.
(9) Apply a thin coat of adhesive to the cleaned
interior facing (step 3, above) to the edges of the
honeycomb core and to the back of the plug patch
(10) Insert the honeycomb core into the trimmed
area of the panel and press firmly in place. Place the
plug patch plate in position and press firmly.
(11) Secure the patch plate in position using
1/8 inch domed head blind rivets (from repair kit),
using procedures given in Section VIII as a guide.
(12) Apply primer and, after primer is dry, re-
paint repair area using paint conforming to Federal
c. Repair to Honeycomb Panel with Damage to
Both Surfaces. Panel damage which penetrates both
surfaces shall be repaired using the procedure given
in paragraph (b), above. Both facings shall be re-