Baby Lock Ovation (BLES8) Instruction and Reference Guide - Manual (Page 53)

Balanced tension -
Cover stitch has correct tension when the needle thread sews
two rows of straight stitching on the top side 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
51
Cover Stitch - Wide - 6mm (Cont.)
Needle thread is too tight
C-1
C-2
C-3
O-1
O-2
UL
* Tension Adjustment
Needle thread is too loose
Balanced tension
∧
∨
underside
top side