ASTM D1646 Specimen Cutting Die (Upper)

ASTM D1646 Specimen Cutting Die — Upper Half (CCSi-D1646-UN)

The CCSi ASTM D1646 Upper Die cuts the second of the two specimen pieces needed for Mooney Viscometer testing under ASTM D1646 — the solid disc that closes over the rotor once the lower half’s orifice is in place.

Where the lower half is die-cut with a central hole for the rotor shaft, the upper half is a plain, uninterrupted disc. Under the heat and pressure of the Mooney die cavity, it presses down against the lower piece and the two fuse into a single homogenous mass, with the rotor now fully sealed inside — the setup that lets the instrument measure shearing torque, stress relaxation, and any pre-vulcanization increase in torque as the compound is worked.

Because the combined volume of the two halves has to land at 25 ± 3 cm³, getting this disc’s mass right (adjusted to ± 3 g based on the material’s known density) matters just as much as getting the lower half’s geometry right — an oversized or undersized upper disc throws off the whole capsule.

CCSi cuts both halves from the same American tool steel stock, wire-EDM finished for long-term resharpening without losing dimensional accuracy. The matching lower half, with its rotor-shaft orifice, is sold separately as the ASTM D1646 Specimen Cutting Die (Lower).