Maintaining And Sharpening; Saw Chain - Stihl HT 70 Instruction Manual

Maintaining and Sharpening

Saw Chain

Correctly sharpened chain
A properly sharpened chain slices
through wood effortlessly and requires
very little feed pressure.
Do not work with a dull or damaged saw
chain as it will increase the physical
effort required, produce unsatisfactory
results and a higher rate of wear.
:
Clean the chain.
:
Check the chain for cracks in the
links and damaged rivets.
:
Replace any damaged or worn parts
of the chain and match the new
parts to the shape and size of the
original parts by filing back as
necessary.
It is necessary to comply with the
angles and dimensions specified
below. If the saw chain is
incorrectly sharpened – especially
if the depth gauges are too low –
there is an increased risk of
kickback and resulting injury!
HT 70, HT 75
The pruner's saw chain cannot be
locked in place on the guide bar.
Therefore, it is best to remove the
chain from the bar and resharpen it
on a workshop sharpening tool
(FG 2, HOS, USG).
:
Select the appropriate sharpening
tools for the chain pitch.
See "Specifications" for the
permitted chain pitches.
3/8
The chain pitch (e.g. 3/8) is marked on
the depth gauge of each cutter.
Use only special saw chain files!
Other files have the wrong shape and
cut.
Select the file diameter according to the
chain pitch (se table "Sharpening Tools"
at the end of this chapter).
You must also observe the following
angles when resharpening the chain
cutters.
A
B
A = Filing angle
B = Side plate angle
Chain type
Picco Micro Mini (PMN)
Cutter shape: Micro = Semi-chisel
Specified angles A and B are more
readily obtained if recommended files or
sharpening tools and correct settings
are used.
english
Angle (°)
A B
30 85
37