The edge crush test (ECT) using a short column specimen is an important test for the boxmaker. Procedures for making the test are discussed in TAPPI T 811 Edgewise Compressive Strength of Corrugated Fiberboard (Short Column Test). For accurate and reproducible results these procedures should be followed in detail. A critical point of the method is cutting the test specimen with sharp parallel cuts exactly perpendicular to the faces. If cutting is by means of a circular saw as prescribed, the saw blade must be small tooted, no-set, and hollow or taper-ground. To improve the saw cut, the saw blade opening (throat plate) in the table saw bed should be as small as possible. This reduces chatter of the corrugated board as it is being cut. Sharp-knife cutters in use in Europe and Japan have been found to give satisfactory cuts for single-wall and lightweight double-wall. Single bevel knife blades are necessary in these cutters.
For referee purposes, the test specimen should have its edges reinforced with paraffin to prevent edge failures per T 811. However, for routine control, other types of sample holders or those used in Japanese standard method may be adequate. (Ref. TAPPI UM 817).
