ASME B18.6.3 — Machine Screws, Tapping Screws, and Metallic Drive Screws
Standard: ASME B18.6.3
ASME B18.6.3 covers inch-series machine screws and tapping (sheet metal) screws — dimensions, head types, and drive recesses below 1/4 in.
What It Covers
- Machine screw sizes #0–#12
- Pan, flat, round, and truss heads
- Tapping screw types A, AB, B, 25
- Slotted, Phillips, and hex drives