It is necessary to adjust the thread tension for the seams shown below.
[ ADJUSTING THE NEEDLE THREAD TENSIONS ]
The left needle thread tension is too loose.
Back side
Front side
Tighten the left needle thread tension.
[ ADJUSTING THE LOOPER THREAD TENSIONS ]
The lower looper thread is tight and/or
the upper looper thread is loose.
Back side
Front side
Loosen the lower looper thread tension
and/or tighten the upper looper thread
tension.
The right needle thread tension is too loose.
Back side
Front side
Tighten the right needle thread tension.
The upper looper thread is tight and/or
the lower looper thread is loose.
Back side
Front side
Loosen the upper looper thread tension
and/or tighten the lower looper thread
tension.
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