This selection guide is designed as a general overview of the many durometer styles, types, spring force ranges, and indentor configurations.
It may assist in choosing the proper durometer for a particular application, however, it is not to be considered a definitive technical document.
It is also highly recommended that, whenever possible, an operating stand be employed in performing durometer hardness tests.
Rex Operating Stands:
Rex OS-1 | Rex OS-2 | Rex OS-2H | Rex OS-3 | Rex OS-4 | Rex OS-4H
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ASTM Type | Application | Model | Spring (gf) | Indentor Geometry |
A | Rubber: Soft vulcanized, natural, nitrile | Elastomeric Materials: neoprene, thiokol, flexible polyacrylic esters | Other: Wax, felt, leather, etc. | DD-4 | DD-5 | 3000 | 4000 | 5000 | H-1000 | 1500 | 1600 | 2000 | 2100 | 822 | 35º Truncated Cone |
B | Rubber: Moderately Hard (typewriter rollers, platens) | DD-4 | DD-5 | H-1000 | 1500 | 1600 | 2000 | 4536 | 30º Cone |
C | Rubber: Medium Hard | Plastics: Medium Hard | DD-4 | DD-5 | H-1000 | 1500 | 1600 | 2000 | 4536 | 35º Truncated Cone |
D | Rubber: Hard | Plastics: Harder grades; Rigid Thermoplastics | DD-4 | DD-5 | 3000 | 4000 | 5000 | H-1000 | 1500 | 1600 | 2000 | 4536 | 30º Cone |
E | Soft Rubber | DD-4 | DD-5 | H-1000 | 1600 | 822 | 2.5mm spherical |
DO | Textile Windings: Very Dense (slasher beams, etc.) | DD-4 | DD-5 | H-1000 | 1500 | 1600 | 2000 | 4536 | 3/32” Sphere |
O | Rubber: Soft | Textile Windings: Medium Density | DD-4 | DD-5 | H-1000 | 1500 | 1600 | 2000 | 822 | 3/32” Sphere |
OO | Rubber: Sponge | Textile Windings: Low Density | DD-4 | DD-5 | 1600 | 113 | 3/32” Sphere |
OOO | Rubber: Sponge | Plastic: Foams | DD-4 | DD-5 | 1600 | 113 | 1/2” Sphere |
OOO-S | Rubber: Sponge | Plastic: | DD-4 | DD-5 | 1600 | 113 | 1/2” Sphere |
M | Rubber: Soft vulcanized, natural, nitrile | Elastomeric Materials: neoprene, thiokol, flexible polyacrylic esters | Other: Small irregular shapes 1.25 mm+ thick | DD-4 | DD-5 | 1600 | 78 | 30º Cone |
ASKER C | Rubber: Soft vulcanized, natural, nitrile | Elastomeric Materials: neoprene, thiokol, flexible polyacrylic esters | Other: Wax, felt, leather, etc. | DD-4 | DD-5 | 1600 | 855 | 2.54mm spherical |
Rex Durometer, Rex Durometers, Shore hardness, pocket durometer, Shore scale, hardness, rubber hardness, plastic, plastic hardness, indentation hardness, ebonite, ebonite hardness, rubber hardness testing, rubber testing, hardness testing, durometer hardness, testing, ASTM D2240, D2240, ASTM D1957, ISO 868, ISO 7619, JIS K6253, JIS K6251, JIS K6252, JIS K 6253, JIS K6254, JIS K6255, JIS K6256, JIS K6257, JIS K6258, JIS K6259, JIS K6260, DIN 53505, DIN 53 505, CNS, K6898, BS 903, BS 2782, BS ISO 21509, BS EN ISO 868, GB/T 10807, Asker, Asker C, SRIS0101, MIL-STD-45622A, MIL-I-45208A, MIL-STD-120, 83.060, 83.080.01, hysteresis, creep, Young’s Modulus.