Craftsman 151.98835 Operator's Manual page 24

CHAIN MAINTENANCE
Know your saw chain (See Figure 46-47,
page xi)
Use only a low-kickback chain on this saw
(Fig. 47). This fast-cutting chain provides
kickback reduction when properly maintained.
For smooth and fast cutting, maintain the
chain 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 the chain, consider
the following:
■ Improper filing angle of the side plate
(Fig.46) can increase the risk of severe
kickback.
■ Depth gauge setting. (Fig. 49).
■ Edges worn too low increases the potential
for kickback.
■ Cutting edges not low enough decreases
cutting ability.
■ If the chain cutters hit hard objects such as
nails and stones, or are abraded by mud or
sand on the wood, take the saw to a qualified
chainsaw service center to have the chain
sharpened. Use only identical parts as listed
in this manual.
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, take the saw to a qualified
chainsaw service center to have the sprocket
replaced. Use only identical parts as listed in
this manual.
Check the saw chain for possible wear
and damages. Replace it with a new one if
required. Experienced users can sharpen
a dull saw chain (see section "Saw chain
sharpening" below). Refit the saw chain and
the guide bar as described in Replacing the
Guide Bar and Chain section.
NOTE: If you do not fully understand the
correct procedure for sharpening the chain
after reading the instructions that follow,
have the saw chain sharpened by a qualified
chainsaw service center or replaced with a
recommended low-kickback chain.
CARE AND MAINTENANCE
24 ― English
SAW CHAIN SHARPENING
Have your chain sharpened professionally
at a qualified service center, or sharpen the
chain yourself by using a proper sharpening
kit. Also observe the sharpening instructions
supplied with the sharpening kit.
The height difference between the cutting tip
and the ridge is the depth gauge setting.
(Fig. 49).
When sharpening the saw chain you have to
consider the following points:
■ File angle
■ Cutting angle
■ File position
■ Diameter of round file
■ File
TO SHARPEN THE CHAIN, PROCEED AS
FOLLOWS:
■ Use protective gloves.
■ Ensure the chain is correctly tensioned on
the guide bar.
Use a round file, whose diameter is 1.1 times
the cutting tooth depth.
Make sure 20% of the file diameter is above
the cutter's top plate.
A file guide is available from most reputable
tool merchants and is the easiest way to hold
the file at the correct position.
File at an angle perpendicular to the bar, and
at an angle of 25° to the direction of travel.
(Fig.48)
File each tooth from the inside towards
outside only.
File one side of the chain first then turn the
saw around and repeat the process.
Sharpen each tooth equally by using the
same number of strokes.
Keep all cutter lengths equal (Fig. 49).
Check the depth gauge settings every 5
sharpenings. It is essential to keep the depth
gauge settings at .025 inch (Fig. 49).