A band knife is a power tool used for cutting cloth. Very similar in operation to a band saw it has an endless loop blade and the material to be cut is supported by a flat table.
Band Knife blades also have applications for cutting / slitting or converting foam, band knife blades are also used for splitting leather, paper, EVA / Rubber and Carpets.
Band Knife blades are used on 2 types of machines depending on the material being cut / processed. 1) Vertical band knife machine 2) Horizontal band knife machine
On a vertical band knife machine usually a narrow width band knife blade is used. The most common width being 10mm. The length of the band knife blade depends on the supplier of the band knife machine. The dimensions are indicated on a small metal tag pasted or riveted on the machine. The vertical machine band knife blade is most commonly twisted 180 Degrees to enable cutting while advancing the table and also while retracting the work table. Productivity is enhanced when the operator cuts both while advancing and also while retracting the work table after adjusting the foam block after each pass for cutting.
It has been observed that a narrow width on a vertical band knife machine gives better dimensional accuracies on the foam block. The wider the vertical machine band knife - more the deflection and size variation from one end to the other extreme end.
Horizontal band knife blades are wider usually 30mm wide for foam converting is popular, for leather goods 50mm wide blade is popular, 85mm width is popular for the tannery splitting band knife. Ofcourse there are other widths depending on the machine manufacturer.
The horizontal machine band knife blade is supported by a guide to give dimensional accuracies while cutting /splitting.
For both the vertical and horizontal band knife machines there is a grinding attachment which continuously sharpens the band knife while it is cutting. It is possible to find a non powered grinding attachment for the vertical machines but for the horizontal band knife machine the grinding attachment for continuously sharpening the blade is powered by electric motors.