TM 10-3530-207-14
Table 3-1.
Operator Troubleshooting - continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
CLOTHING SEWING MACHINE
11.
STITCHES SKIP OR FAIL TO LOCK.
NOTE
The most common cause of fail-to-lock or skipped stitches is using the wrong needle for the fabric being sewed.
Always use the correct size, class, and variety needle recommended for the fabric being worked.
Step 1.
Check that needle size, class, and variety is right for the fabric being worked.
If needle is incorrect, replace needle with new needle of correct size, class and variety (paras. 2-11a
and 2-11b).
Step 2.
There may not be enough pressure on the presser foot for the fabric being worked.
Vary pressure of presser foot using pressure regulator to try and correct trouble:
Step 3.
You may be pulling on the fabric while stitching.
Do not pull on fabric while stitching. Let the feed dogs move the fabric under the needle. You should
only guide the fabric while stitching.
Step 4.
Check that needle is not blunted or bent.
If blunted or bent, replace needle with a new needle of correct size, class, and variety
(paras. 2-11a and 2-11b).
NOTE
Even if you see nothing wrong with the needle, it may have accumulated lint or sizing from the fabric. This can
happen with certain synthetics and permanent press fabrics or in stitching through adhesives. Clean the needle
or change it if this problem is suspected.
Step 5. Needle bar is out of adjustment.
Notify next higher level of maintenance.
3-15
