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Library › Hardware › Flat-head wood screws, inch #4–#14 (ASME B18.6.1): body and head…

#8 flat-head wood screw envelope

#8 flat-head wood screw envelope: head Ø8.43 mm (A max .332 in) tapering to the Ø4.166 mm nominal body over 2.54 mm (H ref .100 in); plain body, example overall length 1-1/2 in (38.1 mm, Xem's choice); no thread, slot, recess or point

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

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Dimensions

screw ##8
TPI15
nominal body dia (in).164
nominal body dia (mm, computed)4.17
body dia max / min (AFT, in).168 / .157
flat head dia A max / min (in).332 / .292
head height H ref (in).100
pilot softwood / hardwood (Albany, in)7/64 / 1/8
clearance (Albany, in)11/64
pilot softwood / hardwood (Fine Power Tools, in)5/64 / 7/64
clearance (Fine Power Tools, in)11/64
pilot hardwood / softwood (Engineers Edge, in)3/32 / 5/64
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From the full sheet

Flat-head wood screws, inch #4–#14 (ASME B18.6.1): body and head diameter, pilot and clearance holes from three sources + envelope models: every size, notes, mating features and sources. What drill size for a #8 wood screw pilot and clearance hole, and what are the body and head diameters?

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