Technical Info
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Bolt Length Estimation Table for F3125 Grade A325 and A490 Bolts
This table can be used as a guide for bolt length estimation for our structural bolts. Add the length below to grip to determine bolt length required. If beveled washers are used, add an additional 5/16 inch to the no washer column for each bevel washer. If you have any questions, please contact our sales team.Screen reader support enabled.
| Nominal Bolt Diameter | No Washer | One Washer | Two Washers |
|---|---|---|---|
| 1/2 | 11/16 | 55/64 | 1 3/64 |
| 5/8 | 7/8 | 1 1/32 | 1 3/16 |
| 3/4 | 1 | 1 5/32 | 1 5/16 |
| 7/8 | 1 1/8 | 1 9/32 | 1 7/16 |
| 1 | 1 1/4 | 1 13/32 | 1 9/16 |
| 1 1/8 | 1 1/2 | 1 21/32 | 1 13/16 |
| 1 1/4 | 1 5/8 | 1 25/32 | 1 15/16 |
| 1 3/8 | 1 3/4 | 1 29/32 | 2 1/16 |
| 1 1/2 | 1 7/8 | 2 1/32 | 2 3/16 |
