Customer review 9.6!Cutting foam with a band knife: which knife suits your machine?
Cutting foam and foam rubber on a bandsaw? Whether your machine has a sharpening unit decides the band knife: Edge, 14TPI, Wavy or Scallop.
Foam and foam rubber are cut most cleanly on a bandsaw machine with a band knife. A band knife cuts with a ground edge instead of set teeth, so no fibres form along the cut. Which band knife you choose depends mainly on one question: does your machine have a sharpening unit?
With a sharpening unit: Band knife Edge or Band knife 14TPI
A sharpening unit keeps the knife sharp while the machine runs. The two knives with a straight cutting angle belong on such a machine. Band knife Edge is for foam, insulation material, leather, packaging material and textiles. It is less aggressive and can therefore pull slightly more on the material.
Band knife 14TPI has a toothed profile without set and cuts more aggressively, without pulling on the material. It is made for foam, sponge, polystyrene, rock wool, leather, textiles and other types of foam.
Without a sharpening unit: Wavy or Scallop
Wavy has a wavy profile, Scallop a scalloped profile. Neither pulls on the material, and because they don't need a sharpening unit, maintenance is simpler. Scallop is the more aggressive of the two, for heavier work. Wavy is milder, for material that must not be damaged.
| Band knife | Profile | Sharpening unit needed | Cutting edge |
|---|---|---|---|
| Band knife Edge | straight cutting angle | yes | DBSE or DBDE |
| Band knife 14TPI | straight cutting angle, toothed without set | yes | DBSE or DBDE |
| Wavy | wavy | no | DBSE |
| Scallop | scalloped | no | DBSE |
What do DBSE and DBDE mean?
DB stands for double bevel: the edge is ground from both sides. With SE, single edge, there is a cutting edge on one side of the knife; with DE, double edge, on both sides. Your machine determines which one you need. Check your old knife or the manual.
An ordinary bandsaw blade for foam
If you don't have a band knife machine but an ordinary bandsaw, foam can also be cut with a toothed Flexback blade. The cut can then be less smooth than with a band knife. Whether a band knife fits your machine depends on the machine; ask us if in doubt.
Sizes, speed and tension
Our band knives are made of chrome steel, 0.50 mm thick, in 10, 13, 15, 19 and 25 mm widths. The standard versions have an edge hardness of 50 HRC; Scallop is also available as a hard edge version in 15 mm. For foam and foam rubber, our table gives a cutting speed of 900 to 1,800 metres per minute, for Band knife Edge, Band knife 14TPI and Flexback. The tension for band knives is 15,000 to 20,000 PSI.
Ordering your band knife
We make every band knife to size, in any length from 500 to 12,000 mm. On the product page, enter the length and choose the width and cutting edge. All band knives are in the Foam & Foam Rubber collection; other materials in which bandsaw blade for which material. Not sure which knife your machine takes? Ask us.