2340CV
 |
FAQs & Troubleshooting |
Differential feed adjustment
This machine is equipped with two sets of feed dogs under the presser foot to move the fabric through the machine. The differential feed controls the movement of both the front and the rear feed dogs. When set at 1, the feed dogs are moving at the same speed (ratio of 1). When the differential feed ratio is set at less than 1, the front feed dogs move slower than the rear feed dogs, stretching the fabric as it is sewn. This is effective on lightweight fabric that may pucker. When the differential feed ratio is set at greater than 1, the front feed dogs move faster than the back feed dogs, gathering the fabric as it is sewn. This function assists in removing the rippling when serging stretch fabrics.
To adjust the differential feed.
- Locate the differential feed adjustment lever on the left side of the machine.
- The normal setting is 1.0 on the differential feed adjustment lever.
-
To set less than 1.0, move the lever back.
-
To set greater than 1.0, move the lever forward.
| Feed ratio | Main feed (rear) | Differential feed (front) | Effect | Application |
|---|---|---|---|---|
| 0.7 – 1.0 |  |
 |
Material is pulled tight. | Prevents thin materials from puckering |
| 1.0 |  |
 |
Without differential feed. | Normal sewing |
| 1.0 – 2.0 |  |
 |
Material is gatheredor pushed together. | Prevents stretch materials from stretching or puckering |
An example where adjustment is required
When stretch material is sewn without using the differential feed, the material will be wavy.
To make the material more smooth, adjust the feed ratio from 1.0 toward 2.0.
(The feed ratio required depends on the elasticity of the material.)
The more elastic the material, the further toward 2.0 the differential feed ratio should be set. Test sew with a scrap of the fabric to find the correct adjustment.
When sewing thick non-stretchable material such as denim, do not use the differential feed as it may damage the fabric.
