Library › Hardware › Hex lag screws 5/8, 3/4, 7/8 and 1 in (ASME B18.2.1): head width and…

5/8 hex lag screw envelope

5/8 hex lag screw envelope: hex head 0.9375 in across flats (basic) × 0.4219 in high (basic) on a plain Ø15.88 mm (5/8 in nominal) shank, example length 4 in (101.6 mm) under the head (Xem's choice); no thread, chamfer, washer face 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)5/8
TPI5
shank E max / min (in).642 / .605
across flats F, basic15/16
F max / min (AFT).938 / .906
F (Engineers Edge)15/16 (.938 / .906)
across corners G max / min (AFT)1.083 / 1.033
head height H, basic27/64
H max / min.444 / .378
shoulder S min (AFT).312
shank hole (Fastenermart)5/8
pilot, softwood III & IV5/16
pilot, medium II13/32
pilot, hardwood I29/64
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From the full sheet

Hex lag screws 5/8, 3/4, 7/8 and 1 in (ASME B18.2.1): head width and height, shank, pilot holes + envelope models: every size, notes, mating features and sources. What size is the head of a 3/4 lag screw, and what pilot hole does a 5/8 lag bolt need?

Other sizes