Dropped Stitches

A Dropped Stitch is a common mechanical error in machine knitting where a stitch slips off a needle hook or fails to be knitted through by the carriage, resulting in an open loop that ladders down the fabric. Diagnosing and correcting dropped stitches is an essential skill for troubleshooting machine operation.

Common Causes

Dropped stitches are rarely random and are almost always caused by issues with weights, the sponge bar, needle damage, or yarn tension.

1. Insufficient or Uneven Weight

Knitting machines require vertical downward tension to pull the knitted loops down so the needle latches can open and clear the old stitches.

• Selvage Drops: Dropping stitches at the edges (selvages) is usually caused by lack of weight at the sides of the fabric. Claw weights must be hung at the very edges of the knitting and moved up every 10–15 rows as the work progresses.
• Bunching Fabric: If fabric is not weighted properly, it rides up with the needles, preventing the latch from opening. Stitches collect on the needle shank and drop off.

2. Decayed Sponge Bar (Needle Retainer Bar)

The sponge bar holds the needles flat against the needle bed. If the foam inside the bar degrades and loses its bounce:

• The needles bounce or wobble as the carriage cams pass over them.
• The carriage fails to catch the needles at the proper angle, causing stitches to drop randomly across the bed.
• Replacing a flat sponge bar is the first diagnostic step when experiencing persistent dropped stitches.

3. Needle Damage

If dropped stitches occur consistently on the same needle or column:

• The latch of that specific needle may be bent, stiff, or broken, preventing it from closing to lock the new yarn loop.
• The hook may be slightly bent or rough, catching the fibers.
• Stiff latches should be cleaned, oiled, or replaced immediately.

4. Yarn and Tension Issues

• Carriage Tension Dial: If carriage tension is too tight, yarn breaks or snaps off the needle. If it is too loose, stitches slip off the hooks.
• Friction and Static: Static or dry yarn clings to the gates or sinkers, failing to drop off. Applying wax to the yarn resolves this friction.
• Carriage Travel: Pushing the carriage too far past the ends of the needles pulls the yarn tight at the selvage, causing the end stitch to pop off.

Correction & Repair

Dropped stitches should be caught immediately. If a stitch drops:

1. Secure the Loop: Catch the live loop with a safety pin or a transfer tool to prevent it from running down further.
2. Latch Up the Stitches: Use a Latch Tool (or latch crochet hook) to re-knit the laddered stitches. Insert the latch tool through the live loop, catch the first horizontal rung above it, close the latch, and pull it through. Repeat up to the top.
3. Rehang on Needle: Rehang the corrected loop onto the corresponding needle hook.