Use and Care Manual

1 2

4/5

Chain type

492 (91PX), 290 (90SG),

291 (90PX)

Files and how to work with them

Use a special saw chain round le for sharpening. Standard

round les are unsuitable.

Type 492 (91PX): Saw chain round le, dia. 5/32” (4.0 mm).

Type 290 (90SG), 291 (90PX): Saw chain round le,

dia. 11/64” (4.5 mm).

The le should cut only when pushed forwards (arrow). Lift

the le when leading it backwards.

First sharpen the shortest cutter. The length of this cutter is

then the standard for all other cutters of the chain.

New saw teeth must be led to the exact same shape as the

used teeth, including on their running surfaces.

File depending on chain type (90° to the guide bar).

A le holder makes le guidance easier. It is marked for the

correct sharpening angle of:

α = 30°

(keep the marks parallel with the chain when ling, see

illustration) and limits the cut depth to the correct 4/5 of the

le diameter.

After having sharpened the chain, the height of the depth

limiter must be checked by means of a chain gauge.

Correct even the smallest excess height with a special at

le (1).

Round off the front of the depth limiter (2).