– 39 –
3) Important points in adjustment
1
Increase the thread take-up amount of the needle thread take-up lever.
Refer to the adjustment values related to the needle thread guide and needle thread take-up lever.
2
Reduce the feed of the looper threads. (Mainly lower looper thread)
Set J, K, L and M for the soft chain distances.
Fine adjustment of J and M is required to produce even stitches.
3
Adjsut the thread tension while checking the appearance and touch of the stitches produced.
1) Minimize the needle thread tension as far as satisfactory tightness of needle thread stitches is ob-
tained.
2) Increase the upper looper thread tension as much as possible.
4
If the chain-off thread does not stretch satisfactorily, and if it is not satisfied, proceed with the following.
1) Increase the upper looper thread tension.
2) Further increase distances J and K.
3) Further increase the upper looper thread tension.
4) Increase the lower looper thread tension to a maximum as far as good tightness of needle thread
stitches is maintained.
5) Increase the thread take-up amount. If the needle thread is poorly tensed, increase the needle thread
tension.
5
Fine adjustment for producing stitches with better appearance and touch
1) If the knotting point varies at high or low sewing speed, slightly reduce L, and increase the lower looper
thread tension.
2) If a knot is made at a high point, increase J and I.
3) If the needle thread is likely to break, decrease the thread take-up amount and lower the needle thread
tension.
6
Pay attention to the following
1) Minimize the needle thread tension as far as satisfactory tightness of needle thread stitches is ob-
tained.
2) The knot of upper and lower looper threads should be made near the upper edge of a material.
3) Minimize the lower looper thread tension as far as even stitches are maintained.
4) For a safety stitch machine, adjust the soft chain making mechanism so that uniform chain-off thread
is produced during double-chain stitching and overlocking.
Soft chain stitches
Standard stitches
The value given in ( ) parentheses is
the adjustment value for the safety
stitch machine. (Unit : mm)
Looper thread
take-up (left)
Looper thread
take-up (right)
Lower looper
thread take-up
Lower looper
thread guide
Upper looper thread
guide (middle)
Upper looper thread guide (upper)
Upper looper thread guide (right)
O
11
M
29 (27.5)
N
27 (20)
G
17.5
K
15 (12)
E
22
I
26.5
F
65
H
43.5
J
38
(34)
L
6.5
Looper thread should not be
loosened and stretch well
The looper thread loosens
When the chain-off
thread is pulled.
When the chain-off
thread is pulled.
Содержание MO-6700D Series
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