The recommended specimen for molding materials is 127 by
12.7 by 3.2 mm (5 by
1
⁄
2
by
1
⁄
8
in.) tested flatwise on a support
span, resulting in a support span-to-depth ratio of 16 (tolerance
6
1). Thicker specimens should be avoided if they exhibit
significant shrink marks or bubbles when molded.