Samples (test rods) can be processed by injection molding, extrusion, calendaring, or compression molding. Typically, injection-molded samples will have a hardness 2-4A higher than other samples.

3.2. Ambient Testing Temperature

The standard temperature is 23°C. Comparatively, in winter at 0°C and in summer at 30°C, the test results in summer are generally 2-5A lower than in winter. Even if stored under conditions of 23°C for 1 hour, there is still a deviation of 1-3A between winter and summer.

3.3. Reading Time during Testing

Typically, the reading is taken 1 second after the hardness tester makes steady contact with the sample surface. The reading is highest at this point and decreases to its minimum after 15 seconds, with a difference of approximately 2-6A between them.

3.4. Applied Weight (Force) during Testing

When using a fixed support during testing, a fixed weight of masses can be added, maintaining a constant force. However, if a handheld hardness tester is used, the force applied to the sample surface varies among individuals, resulting in a deviation of roughly 2-5A, especially for softer hardness.

3.5. Contact Speed between Hardness Tester and Sample Surface during Testing

Excessive or insufficient force applied during testing can lead to hardness deviations, resulting in a deviation of approximately 1-2A.

4.1. Conversion Formula

A = 0.173D + 86.58

For example, how to convert Shore D38 to Shore A? Shore A = 0.173 × 38 + 86.58 = 93.154.

4.2 Conversion Coordinate Chart