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#8 socket head cap screw envelope

#8 socket head cap screw envelope: head Ø6.86 mm (A max 0.270 in) x 4.17 mm (H max 0.164 in), hex socket 9/64 in across flats x 0.077 in deep (key engagement min), plain Ø4.166 mm shank (D max), example length under the head 0.5 in (Xem's choice); no thread, top chamfer, fillet or socket cone

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

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Dimensions

size#8
TPI UNC / UNF32 / 36
body D max / min (in)0.1640 / 0.1585
head A max / min (in)0.270 / 0.262
head height H max / min (in)0.164 / 0.159
hex socket nominal9/64 in
key engagement T min (in)0.077
wall min (in)0.056
fillet transition dia max / min (in)0.188 / 0.173
top chamfer max (in)0.014
bottom chamfer max (in)0.008
basic thread length LT (in)—
D max (mm, computed)4.166
head dia x height max (mm, computed)6.86 x 4.17
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From the full sheet

Socket head cap screws, inch #0 to 1-1/2 (ASME B18.3): head, hex socket, key engagement — full size table + models #0 to 1: every size, notes, mating features and sources. What are the head diameter, head height and hex key size of a #4-40, #8-32, 1/4-20, 5/8-11 or 1 in socket head cap screw?

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