CHAIN TENSION AND MAINTENANCE
CHAIN TENSION
Stop the engine before setting the chain tension. Make sure the guide
bar screw is loosened to finger tight, turn the tensioning wheel up or
down to tension the chain. A cold chain will be correctly tensioned
when there is no slack on the underside of the guide bar, the chain is
snug, but it can be turned by hand without binding.
Chain must be re
-
tensioned whenever the flats on the drive links hang
out of the bar groove.
During normal saw operation, the
temperature of the chain will
increase. The drive links of a
correctly tensioned warm chain will
hang approximately .050 in.
(1.25mm) out of the bar groove. Be
aware that chain tensioned while
warm, may be too tight upon
cooling. Check the “cold tension”
before next use.
NOTE:
A new chain tends to stretch, check chain tension frequently
and tension as required.
CHAIN MAINTENANCE
CAUTION:
Disconnect from the power supply and make sure the
chain has stopped before you do any work on the saw.
For smooth and fast cutting, chain needs to be maintained properly.
The chain requires sharpening when the wood chips are small and
powdery, the chain must be forced through the wood during cutting,
or the chain cuts to one side. During maintenance of your chain
remember:
-
Improper filing angle of the side plate can increase the risk of
severe kickback.
-
Raker (depth gauge) clearance.
-
Too low increases the potential for kickback.
-
Not low enough decreases cutting ability.
-
If cutter teeth have hit hard objects such as nails and stones, or
have been abraded by mud or sand on the wood, have service dealer
sharpen chain.
NOTE:
Inspect the drive sprocket for wear or damage when replacing
the chain. If signs of wear or damage are present in the areas
indicated, have the drive sprocket replaced by a qualified individual.
Call our customer service help line at 1
-
800
-
313
-
5111 for assistance.
HOW TO SHARPEN THE CUTTERS
Be careful to file all cutters to the
specified angles and to the same
length, as fast cutting can be
obtained only when all cutters are
uniform.
Wear gloves for protection.
Properly tension the chain prior to
sharpening. Refer to “Chain Tension Section” earlier in this manual.
Do all of your filing at the midpoint of the bar.
Use a 5/32 in. diameter round file and holder.
Keep the file level with the top
plate of the tooth. Do not let the
file dip or rock. Using light but
firm pressure, stroke towards
the front corner of the tooth.
Lift file away from the steel on each return stroke.
Put a few firm strokes
on every tooth. File all
left hand cutters in one
direction. Then move to
the other side and file
the right hand cutters in
the opposite direction.
Occasionally remove
filing from the file with a wire brush.
WARNING:
Improper chain sharpening increases the potential of
kickback.
WARNING:
Failure to replace or repair damaged chain can cause
serious injury.
WARNING:
The saw chain is very sharp, always wear protective gloves
when performing maintenance to the chain.
TOP PLATE FILING ANGLE
Correct 30 degrees – File holders
are marked with guide marks to
align file properly to produce top
plate angle.
Less than 30 degrees – for cross cutting.
More than 30 degrees – feathered edge dulls quickly.
SIDE PLATE ANGLE
Correct – 80 degrees produced
automatically if correct diameter
file is used in file holder.
Hook – “Grabs” and dulls quickly. Increases potential of kickback.
Results from using a file with a diameter too small, or file held too low.
Backward Slope – Needs too much feed pressure, causes excessive
wear to bar and chain. Results from using a file with a diameter too
large, or file held too high.
DEPTH GAUGE CLEARANCE
The depth gauge should be main-
tained at a clearance of .025 in. (0.6
mm). Use a depth gauge tool for
checking the depth gauge clearances.
Every time the chain is filed, check the
depth gauge clearance
Use a flat file and a depth gauge joint-
er to lower all gauges uniformly. Depth
gauge jointers are available in .020 in.
to .035 in. (0.5 mm to 0.9 mm). Use
a .025 in. (0.6 mm) depth gauge joint-
er. After lowering each depth gauge,
restore original shape by rounding the
front. Be careful not to damage adjoin-
ing drive links with the edge of the file.
Depth gauges must be adjusted with the flat file in the same direction
the adjoining cutter was filed with the round file. Use care not to contact
cutter face with flat file when adjusting depth gauges.
Approx. .050 (1.25mm)
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