TM 5-1940-321-13&P
( 3 ) Fit the patch without glue first to ensure the patch is the correct size. The patch
should extend at least 2 inches in all directions from the tear.
( 4 ) Glue the inner patch into position in two separate steps. First glue the lower lip
of the tear onto the inner patch, then glue the upper lip of the tear onto the
inner patch.
( 5 ) Smooth down any slight separation between the two edges of the tear by
rubbing with a clean towel soaked in solvent.
( 6 ) Beginning at the most difficult end of the tear, assemble the inner patch to the
craft with the glue dry. Reactivate the glue with solvent, one section at a time
as you proceed.
g. Tear in Buoyancy Tube at a Baffle. Tears that occur at the internal baffles between air
chambers are repaired using the technique of applying a single outer patch only. Inner patches are not
necessary on baffles since the baffle is not an air seal between the air chamber and the atmosphere.
( 1 ) An unglued or torn flange between the baffle and the inside surface of the tube
is glued from the buoyancy tube wall to the baffle itself.
( 2 ) To patch a hole in a baffle or chamber, a patch cut on the fabric bias is used.
The patch is placed on one side of the baffle only. No inner patch is necessary
to repair a baffle.
( 3 ) A new or repaired baffle flange will be glued on an internal patch which will fit
over the tear. This is one of the most difficult repair operations, in view of the
limited working space. The patches should lau flat against the surface and not
fold or blister.
( 4 ) The tear will be sealed by gluing onto the interior patch which is not glued on
both sides. All scuffing and cleaning with solvent is done in advance.
( 5 ) After waiting 24 hours, test the pressure in the two adjacent air compartments
and test the tear for leaks with soap and water ( chapter 6, paragraph 6-3). An
external patch is then applied which should, if possible, take the shape of a
small panel.
F-22
