Skipped Stitches
If your machine is skipping stitches, zigzag stitches will look like a straight stitch on
either the right or left side with proper zigzag stitches being formed only occasionally.
Straight stitches will have stitch lengths that look exceptionally long at times.
A skipped stitch means the gib hook is not catching the thread consistently.
There are a number of causes for skipped stitches.
Start with Step 1 and stop as soon as the problem is resolved.
1. Incorrectly Installed, Bent, or Dirty Needle
A bent needle will cause skipped stitches because the loop is not where the gib hook
(p. 55,
16
) “expects” it to be. Adhesive residue on the needle will cause the thread to stick
to the needle instead of moving through the eye to form a loop.
Make sure your needle is installed correctly (p. 4), is not bent or damaged, and is free of any
residue from sewing adhesive material. Fouled needles may be cleaned with rubbing alcohol.
Bent or damaged needles must be replaced.
2. Not Enough Foot Pressure
Heavy, closely-woven materials like sailcloth and canvas can make the withdrawal of the
needle from the fabric difficult.
If the presser foot is being lifted as the needle comes out of the cloth the loop that the needle
forms will be too small.
Increase the downward pressure on the presser foot by tightening the pressure regulating
thumb screw (p. 12,
13
).
3. Burred Gib Hook or Retaining Ring Cap Spring (
37
)
A needle strike to the gib hook (
A
) or the edge of the retaining ring cap spring’s “triangular”
opening (
B
) may result in a burr which can cause the thread to snag as it pulls through.
Remove any burrs by polishing them with emery paper or a fine file. If badly damaged,
replace with a new retaining ring cap spring (#1603).
4. Machine Has Gone Out of Timing
If skipped stitches continue, the machine has probably gone out of timing. The timing is
checked by determining the relationship of the needle to the gib hook point.
To reset the timing on your Ultrafeed
®
, follow the steps outlined on p. 40 "Ultrafeed
®
Timing".
Burred Area
Burred Area
>
Retaining Ring Cap Spring
>
Gib Hook
37
A
B
Ultrafeed
®
Guidebook: Troubleshooting the Ultrafeed®
32
31
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