17
Chain Tension
Check the chain tension before using the saw when the chain
is cold. The correct tension of a cold chain is when there is no
slack on the underside of the guide bar; the chain is snug, but
you can rotate it by hand without binding.
During normal saw operation, the temperature of the chain will
increase. The drive links of a correctly tensioned warm chain
will hang approximately 0.050 in. (1.25 mm) out of the bar
groove (Fig. 21). Be aware that a chain tensioned while warm
may be too tight upon cooling. Check the “cold tension” before
next use. The chain must be re-tensioned whenever the flats
on the drive links hang out of the bar groove (Fig. 21).
NOTE:
A new chain tends to stretch. Check the chain tension
frequently and re-tension as needed.
Nuts + Screws
Periodically check that all the nuts and screws are securely
tightened and the hand grips are tightly fastened.
Chain Sharpening
m
WARNING!
To ensure that the chain saw works safely
and efficiently, it is essential that the cutting components are
well-sharpened.
It is highly recommended to replace the
chain once it loses its ability to cut cleanly and safely.
It is possible, however, to sharpen the existing chain if the
sharpening is carefully performed. Any work on the chain
and bar requires specific experience and special tools. For
safety purposes, we recommend you contact an authorized
Snow Joe
®
+ Sun Joe
®
dealer or call the Snow Joe
®
+ Sun Joe
®
customer service center at 1-866-SNOWJOE (1-866-766-9563).
Sharpening is necessary when:
• The sawdust looks like dust.
• Cutting becomes more difficult.
• The cut is not straight.
• Vibrations increase.
An authorized service center will sharpen the chain using the
right tools to ensure minimum removal of material and even
sharpness on all the cutting edges.
If you sharpen the chain yourself, use special round-section
files with the diameter of 5/32 inch (4 mm). You need a certain
amount of skill and experience to avoid damaging the cutting
edges.
Sharpen the chain as follows (Fig. 22):
• Secure the bar firmly, with the chain mounted, in a
suitable vice.
•
Tighten the chain if it is loose.
• Mount the file in the guide and then insert it in the tooth at
a constant angle from the cutting edge.
•
Sharpen in a forward motion a few times and repeat this
on all the cutting edges facing the same way (right or left).
• To move the chain forward, use a screwdriver.
•
Turn the bar over in the vice and repeat on all the other
cutting edges.
•
Check that the depth limiter tooth does not stick out
farther than the inspection tool
and file any projecting
parts with a flat file, rounding off the edges (Fig. 2
2).
• After sharpening, remove all traces of filing and dust
and lubricate the chain in an oil bath. Replace the chain
whenever:
–
the length of the cutting edges decreases to 5 mm
or less;
– there is too much play between the links and the rivets.
Fig. 21
Properly Adjusted Warm Chain
Approximately .050 in. (1.25 mm)
Flats are
visible here
Flats are not
visible here
Chain Needs Tensioning
Fig. 22
Inspection tool
Depth limiter tooth
Cutting edge
Depth
limiter
tooth
