3.1 Guide sample. Samples of the end item when furnished, are
solely for guidance and information to the contractor see (6.3).
Variations from this document may appear in the sample, in which
case this document shall govern.
3.2 First article. When specified a sample shall be subjected
to first article inspection (see 4.3, 6.2, and 6.4).
3.3 Materials and components. Materials (see 6.6 and 6.7) and
components shall be as specified on Drawings.
3.4 Construction. The construction shall conform in all
respects to the drawings listed in section 2 and as specified herein.
3.4.1 Stitches, seams and stitchings.
All stitching, shall
conform to FED-STD-751 as follows:
For all stitching
Stitch type 301, 8 to 10 stitches per
220.127.116.11 Type 301 stitching. Ends of stitching shall be
backstitched or over stitched not less than 1 inch except where ends
are turned under or caught in other seams and stitching. Thread
tensions shall be maintained so that there will be no loose
stitching resulting in loose bobbin or top thread or excessively
tight stitching resulting in puckering of the materials sewn. The
lock shall be imbedded in the materials sewn.
3. 18.104.22.168 Repairs of type 301 stitching.
Repairs of type 301
stitching shall be as follows:
a. When thread breaks or bobbin run-outs occur during
stitching, the stitching shall be repaired by restarting the
stitching a minimum of 1 inch back of the end of the stitching.
b. Thread breaks or two or more consecutive skipped or
run-off stitches noted during inspection of the item (in-process
or end item) shall be repaired by overstitching. The stitching
shall start a minimum of 1 inch in back or the defective area,
continue over the defective area and continue a minimum of 1
inch beyond the defective area onto the existing stitching.
Loose or excessively tight stitching shall be repaired by
removing the defective stitching without damaging the materials
and restitching in the required manner. 1/
1/ When making the above repairs, the ends of the stitching are not
required to be backstitched.