 | Wood Harvesting with Hand Tools - An Illustrated Training Manual (ILO, 1989, 128 p.) |
 |  | CROSS-CUT SAWS |
|
|
TYPES OF RAKER-TOOTH CROSS-CUT SAWS
The raker-tooth cross-cut saw is the most efficient type of saw for felling and cross-cutting. This type of saw is recommended for professional use.
There are two types: one raker followed by two cutters (Champion teeth BM1) for harder wood (1) and one raker followed by four cutters (Lance teeth, 4 YM1) for softer wood (2).
1 According to International Organisation for Standardisation.
The raker's work can be compared with that of a plane. It removes the fibres (3b) which are cut on both sides of the kerf by the cutters (3a). The raker must be slightly shorter than the cutters so that it will not break off uncut fibres. However, if too short, it will not sufficiently break loose the cut fibres and the cutters will jam in the kerf. A gullet of sufficient depth is needed to hold and transport the sawdust (3c).
Correct raker depth produces long chips with clean edges (4); if the raker depth is too long, chips tend to have whiskers (5); if too short, fine sawdust is produced.
Figure
Figure
Figure
Figure
Figure
|
|