|Operations on Band and Circular Sawing Machines - Course: Mechanical woodworking techniques. Trainees' handbook of lessons (Institut für Berufliche Entwicklung, 19 p.)|
The tools of band sawing machines are the band saw blades. The are, in point, saw blades combined into an endless band by means of hard soldering or welding, which may be differently arranged in widths, tooth division and height.
Figure 19 Band saw blade 1 teeth division, 2 teeth height, 3 band width
Generally speaking acute-angled teeth are used. Saw blades with a rough teeth division (8-10 mm) are used for sawing soft wood whilst for hard wood and sheet material saw blades with a smaller teeth division (6-8 mm) are employed. The free cutting of the saw blades is ensured through teeth displacement, less frequently also through linear contraction.
Figure 20 Free cut through saw blade linear contraction
Tom saw bands must be resoldered or rewelded prior to sharpening. The free ends are cut rectangularly, cleaned and inclined to lengths between 10 and 15 mm.
- When the ends are soldered together they must be so positioned to one another that the blade backs at the point of connection are not bent and the original teel division is adhered to. The solder point should re-anneal and only cool off gradually; it is hammered, cleanly filed on both sides and ground to normal blade cross-cut.
- The ends are positioned bluntly to one another, welded and subsequently the welding crust is removed during saw blade welding.
New, freshly soldered or welded saw blades operate idle running for five minutes prior to first actual operations!
Saw blades are stored hung up with the teeth to the wall!