Adjusting The Thread Take-Up Amount - Brother T-8421D Instruction Manual

Adjusting the thread take-up
amount
The thread take-up amount is adjusted by how the
thread is passed through the thread amount adjuster
(1).
Using the standard thread amount adjuster (1)
For foundation specifications: Other than
T-8452D-405
• Do not pass the thread through the thread amount
adjuster (1). Loosen the screw (2) and slide the
thread amount adjuster (1) to the right-side position.
For foundation specifications: T-8452D-405
• Pass the thread through the thread amount adjuster
(1). The standard position of the thread amount
adjuster (1) is when the screw (2) is in the center of
the adjustment range.
How to adjust the thread take-up amount
• When the thread has been passed through the
thread amount adjuster (1), the thread take-up
amount becomes less when the thread amount
adjuster (1) is moved to the right.
It is better not to pass the thread through the
thread amount adjuster (1):
- When sewing heavy-weight materials using a
sewing machine with foundation specifications
- When the thread take-up amount is not
enough, such as when the stitch length is
increased
It is better to pass the thread through the thread
amount adjuster (1):
- When sewing with slippery threads such as
polyester threads
- When sewing light-weight materials
- When sewing with a stitch length of 2 mm or
less
- When sewing under any of the above three
conditions and you would like to prevent
skipped stitches, thread tightening problems
such as looping, or thread breakages
Guide to adjustment
• Adjust in accordance with the sewing conditions.
The standard thread take-up amount is when the
thread tension spring (3) starts to move when the
loop is moved to point (B) which is slightly in front of
point (A) where the rotary hook tip catches the
upper thread loop and the rotary hook thread
amount is at its maximum.
Threa Start of movement
d of thread tension
take- spring (3)
up
amou
nt
Too The thread tension
large spring (3) will not start
to move even after
point (A) is passed.
Too The thread take-up
small spring (3) will start
moving before point
(B).
Possible problem
This can cause
skipped stitches, poor
thread tightening and
thread breakages.
This can cause
thread breakages,
overtightening of the
upper thread and
pulling of the seam.
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