Baby Lock Ovation (BLES8) Instruction and Reference Guide - Manual (Page 51)

Balanced tension -
Cover stitch has correct tension when the needle thread sews
two rows of straight stitching on the top side of the fabric and the
chain looper forms a zigzag on the underside of the fabric.
Needle thread is too loose -
Turn the chain /cover stitch needle tension dial to a higher
number.
Or turn the chain/cover stitch looper tension dial away from the
wide stripe at the words "Cover Stitch", but staying within the
solid gold line. This will tighten the chain looper thread on the
underside of the stitch.
Needle thread is too tight -
For a looser tension turn the chain /cover stitch needle tension
dial to a lower number. Make sure that the chain/cover stitch
looper tension dial is set at the solid stripe with the words "Cover
Stitch".
C
H
A
I
N
/
C
O
V
E
R
S
T
I
T
C
H
E
X
P
R
E
S
S
49
Cover Stitch - Left Narrow (Cont.)
Balanced tension
Needle thread is too loose
Needle thread is too tight
C-1
C-2
C-3
O-1
O-2
UL
* Tension Adjustment
∧
∨
underside
top side