20
CZ8000
6.Adjustments of sewing machine
6.4.3 Sharpness of knives
6.4.4 Sharpening knives
After adjusting the knives and the width of overedge seam,
check the sharpness of the blades by setting a thread
between the upper and the lower knives while rotating the
machine pulley by hand.
If the lower knife cuts badly, re-sharpen it. (See Fig. 6-9)
The upper knife made of super hard alloy is unnecessary
to re-sharpen for about one year and normal grinder is
not useful for re-sharpening it.
Keep another upper knife for spare.
If needed, contact us directly or a dealer for re-sharpen-
ing.
Fig. 6-9
thread
10°
55°
Fig. 6-8