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Library › Hardware › Hex cap screws and heavy hex screws, inch 7/8 to 1-1/2 (ASME…

heavy hex screw 1-8 UNC envelope

heavy hex screw 1-8 UNC envelope: hex head 1.625 in across flats x .627 in high (F max, H max), plain shank Ø1.0000 in (major diameter, thread not drawn), 4 in under the head (example length, Xem choice); published thread length LT 2.250 in (L ≤ 6 in)

Exact dimensions. True size, no tolerance added. Threads are plain cylinders at the major diameter.

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Dimensions

styleheavy hex screw
size (in)7/8
UNC / UNF TPI9 / 14
E body dia max / min.8750 / .852
F across flats max / min1.438 / 1.394
G across corners max / min1.660 / 1.589
H head height max / min.563 / .531
J wrenching height min (cap only)–
LT thread length, L ≤ 6 in2.000
LT thread length, L > 6 in2.250
file: F max / H max (mm)36.53 / 14.3
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From the full sheet

Hex cap screws and heavy hex screws, inch 7/8 to 1-1/2 (ASME B18.2.1): across flats F, head height H, thread length LT: every size, notes, mating features and sources. What are the head size, head height and thread length of a 7/8, 1, 1-1/8, 1-1/4, 1-3/8 or 1-1/2 inch hex cap screw or heavy hex screw?

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