Hex bolts (six sided heads) are the industry standard for fasteners with forged heads. ASTM A307 Grade A bolts, all SAE hex bolts, and several other common specifications require a standard (finished) hex head. For specifications such as A307 grade B, A325 and A490 that require a heavy hex pattern, refer to dimensional tolerances for heavy hex bolts or structural bolts.


Manufacturing:

Fastindo Wiratama manufactures lag screws from 1/2″ diameter through 1-1/2″ diameter in most ASTM, AASHTO, and SAE specifications. Special tooling can be created to produce nonstandard head dimensions or bolt heads with your company’s name and/or logo.
Unless otherwise specified, nonstandard lag screws manufactured by Fastindo Wiratama will possess a semi-cone point rather than a gimlet or cone point. A full point is unnecessary since a pilot hole nearly as large as the root diameter of the lag screw will need to be drilled prior to installation. Additionally, a gimlet point is designed for small diameter screws so they can be installed without a pilot hole. Lag screws in diameters listed in the above table do not require a gimlet point since too much torque would be required to install the large screws without drilling a pilot hole first. Without a pilot hole, the heads of the screws will often break before the lag is properly installed.

Stock:

Diameters: 1/2″ – 3/4″
Lengths: 18″ maximum
Origin: Import
Finish: Black and hot-dip galvanized

Standard Thread Length:

The minimum thread length shall be equal to one-half the nominal screw length plus 1/2″ or 6”, whichever is less. One should consider longer than standard thread lengths for lag screws which are extremely long.
Note: Hex lag screws larger than 3/4″ in diameter and all square lag screws are rarely available in the marketplace as a stock item.


Hex Lag Dimensions
Bolt Diameter D F H Threads Per Inch Thread Dimension
Body Diameter Width Across Flats Head Height Pitch TF TD TR
Max Min Flat At Root Depth of Thread Root Diameter
1⁄2 0.515 0.482 3⁄4 11⁄32 6 0.167 0.072 0.064 0.371
5⁄8 0.642 0.605 15⁄16 27⁄64 5 0.200 0.086 0.077 0.471
3⁄4 0.768 0.729 11⁄8 1⁄2 41⁄2 0.222 0.096 0.085 0.579
7⁄8 0.895 0.852 15⁄16 37⁄64 4 0.250 0.108 0.096 0.683
1 1.022 0.976 11⁄2 43⁄64 31⁄2 0.286 0.123 0.110 0.780
11⁄8 1.149 1.098 111⁄16 3⁄4 31⁄4 0.308 0.133 0.119 0.887
11⁄4 1.277 1.223 17⁄8 27⁄32 31⁄4 0.308 0.133 0.119 1.012
13⁄8 1.404 1.346 21⁄16 29⁄32 3 0.333 0.143 0.128 1.119
11⁄2 1.531 1.469 21⁄4 1 3 0.333 0.143 0.128 1.244
Dimensions per ASME B18.2.1 2003

Stock Lag Screws
Length (in.) Diameter
3/8" 1/2" 5/8" 3/4"
Galvanized
2 11384 - - -
21⁄2 11386 - - -
3 11388 11418 11454 -
31⁄2 11390 - - -
4 11392 11422 11458 -
5 11396 11426 - 11498
6 11400 11430 11466 11502
7 - 11434 11470 -
8 11408 11438 11472 11510
10 - 11442 11476 11514
12 - 11446 11480 11518
14 - - - 11522
18 - - - 11530
These sizes are readily available in the marketplace and Fastindo Wiratama stocks many of them in varying quantities. If you require a size that is not listed, Fastindo Wiratama will manufacture them.