The cotton duck (1) and felt (2) fabric of the case may be restitched, darned, patched and plugged.
a. Restitching. Restitch the case fabric (1) directly over old stitching using size 5 thread, 5 to 8 stitches per inch,
and an VHD sewing machine. Lock stitching at least 1/2 inch.
b. Darning. Darn a hole or tear in the case fabric that does not exceed 1 inch in length or diameter using size E
thread and a ZZ darning machine. There is no limit to darns that may be applied, provided they do not weaken or reduce
the original strength of the fabric more than 10%. If damage is in the lined portion of the case and only the cotton duck is
damaged, darn through duck and felt. If felt is also damaged, remove damaged area before darning duck fabric. Then
plug felt as in c.(3) below.
c. Patching. There is no limit to the number of times the case may be patched. Patch a hole or tear that exceeds
1 inch in length or diameter following procedures in (1) or (2) below. Use nylon or cotton duck cloth according to original
construction for patching outside, and 1/4 inch thick felt for plugging inside lining. Use an MD sewing machine, size FF
thread, and 7 to 9 stitches per inch.