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1/2 carriage bolt envelope (ASME B18.5 round head, square neck)

1/2 carriage bolt envelope (ASME B18.5 round head, square neck): spherical-cap head Ø27.79 × 6.86 mm (A max, H max), square neck 13.08 mm wide × 7.14 mm deep (O max, P max), plain shank Ø12.70 mm (nominal) × 76.2 mm (3 in, Xem's example length) under the head; no thread, chamfer, corner radius or point

Exact dimensions. True size, no tolerance added. Threads are plain cylinders at the major diameter.

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Dimensions

size (in)1/2
body E max / min.515 / .483
head dia A max / min1.094 / 1.032
head height H max / min.270 / .250
square width O max / min.515 / .492
square depth P max / min.281 / .250
corner radius on square max.047
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From the full sheet

Carriage bolts, ASME B18.5 round head square neck, #10 to 1 in: head, square neck, body diameter + envelope models: every size, notes, mating features and sources. What are the head diameter and square neck size of a 3/8 carriage bolt, and what hole does the square need?

Other sizes