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Button head bolts (round head) are commonly used in wood connections. Button head bolts are similar to carriage bolts, but without the square neck under the head. Because they are used with wood, button head bolts are rarely high strength and virtually always supplied in a standard ASTM A307 specification.
Portland Bolt manufactures button head bolts from 1/2" through 1-1/4 " diameter in most ASTM, AASHTO, and SAE specifications. Special tooling can be created to produce nonstandard head dimensions, button head bolts larger than 1-1/4" in diameter, or bolt heads with your companies name and/or logo.
Bolt lengths ≤ 6”: Thread length = (2 X diameter) + 1/4”
Bolt lengths > 6”: Thread length = (2 X diameter) + 1/2”
Note: Most stock hex bolts longer than 12” in length will have 6”
of thread.
| Bolt Diameter | D | C | H | |||
|---|---|---|---|---|---|---|
| Body Diameter | Head Diameter | Head Height | ||||
| Max | Min | Max | Min | Max | Min | |
| 3/8 | 0.388 | 0.360 | 0.844 | 0.782 | 0.208 | 0.188 |
| 1/2 | 0.515 | 0.483 | 1.094 | 1.032 | 0.270 | 0.250 |
| 5/8 | 0.642 | 0.605 | 1.344 | 1.219 | 0.344 | 0.313 |
| 3/4 | 0.768 | 0.729 | 1.594 | 1.469 | 0.406 | 0.375 |
| 7/8 | 0.895 | 0.852 | 1.844 | 1.719 | 0.469 | 0.438 |
| 1 | 1.022 | 0.976 | 2.094 | 1.969 | 0.531 | 0.500 |
| 1-1/4* | 1.277 | 2.850 | 0.531 | 0.500 | ||
*Dimensions per ASME B18.5 1990 (R 1998) cover diameters up to 1". Bolts over 1" use custom head dimensions.
