Hex Lag Screws

hex-lag-dim-500

Hex lag screws are used in marine construction involving wood. Lag screws are commonly available as a stock item through 3/4″ diameter. Custom lag screws ranging from 7/8″ diameter through 1-1/2″ diameter in virtually any length can be manufactured. Lag screws are typically hot-dip galvanized mild steel or type 304 or 316 stainless steel. High strength lag screws can be manufactured for special applications.

Click table to show drawing
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 1996
* ASME only provides dimensional data for lag screws through 1¼” diameter. Lag screws over 1¼” diameter use custom thread pitches.