Bernina 380 Manual page 23

Height Compensation of Uneven Layers
Sewing Corners
The feed dog works accurately when the foot is level.
If the foot is at an angle, e.g. when sewing over thick to thin or vice-versa, the
feed dog cannot grip and feed the fabric. The fabric might jam.
To solve this problem, place one, two or three compensating plates as required
behind the needle under the presser foot to level it.
To correct the height in front of the foot, place one or more plates to the right of
the foot close to the needle. Sew until the foot is level again and remove the
plates.
When sewing corners only a small section of the fabric is actually on the feed
dog. Therefore it cannot grip the fabric well.
Correct this by placing one or more compensating plates as close as possible
to the edge of the fabric.
033301.71.04_2014-02_Manual_B330_B350_PE_B380_EN
Preparation - Sewing
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