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Wing screws, inch (type A, cold formed, ASME B18.17 family): #8 to 3/8 in wing spread, height, thickness, boss

How wide is a 1/4-20 wing screw, and how tall are its wings? · Standard part · basis: CDE Fasteners' type A wing screw sheet (ASME B18.6.8-2010 as printed) cross-checked with Tanner Bolt's cold-forged wing nut sheet (ASME B18.17), whose wing and boss dimensions are the same for the shared sizes; numbers only

Also called: wing screw dimensions inch, 1/4-20 wing screw wing span, #10 wing screw size, wing screw 5/16-18 dimensions, 3/8-16 wing screw wing height, cold formed wing screw type a, wing screw boss diameter, butterfly screw size chart, wing bolt dimensions 1/4, asme b18.17 wing screw, wing screw #8-32 wing spread, wing screw thickness

Exact dimensions. True size, with no tolerance added.

sizes
5 in table

Notes

  • Inches (max / min in each cell; the last column converts the maxima of A and B to mm). Sizes #8 to 3/8 in. A wing spread, B wing height, C wing thickness, E boss diameter, G boss height. CDE prints the wing screw table under ASME B18.6.8-2010 (type A: a two-piece screw, cold-formed winged head permanently installed on the shank) and gives length tolerances by nominal length: ±0.03 in up to 1 in, ±0.06 over 1 to 2 in, ±0.09 over 2 in. No lengths are listed on that sheet.
  • Cross-check: Tanner's cold-forged wing nut sheet (the ASME B18.17 table, already tabulated on wing-nuts-din-315-asme-b18-17) prints identical A, B, C, E and G max / min for #8, #10, 1/4, 5/16 and 3/8 (e.g. 1/4: A 1.10 / 0.97, B 0.57 / 0.43, C 0.18 / 0.14, E 0.50 / 0.45, G 0.22 / 0.17). The dimension D (between the wings), printed for wing nuts, is not on the wing screw sheet and is not shown. Types B and C (other head forms) were not found with numbers.
  • No files: the wing outline (curve, cross-section) is not published as numbers in any table read, so no model is drawn. Metric forms: wing-screws-din-316. McMaster-Carr sells wing screws with per-part STEP; linked, not copied.

Wing screws, inch (type A, cold formed, ASME B18.17 family): #8 to… size chart

sizeTPIA wing spread (in)B wing height (in)C wing thickness (in)E boss diameter (in)G boss height (in)mm (max)
#8320.91 / 0.780.47 / 0.340.14 / 0.100.43 / 0.390.18 / 0.14A 23.1 mm, B 11.9 mm
#1024 & 320.91 / 0.780.47 / 0.340.14 / 0.100.43 / 0.390.18 / 0.14A 23.1 mm, B 11.9 mm
1/4201.10 / 0.970.57 / 0.430.18 / 0.140.50 / 0.450.22 / 0.17A 27.9 mm, B 14.5 mm
5/16181.25 / 1.120.66 / 0.530.21 / 0.170.58 / 0.510.25 / 0.20A 31.8 mm, B 16.8 mm
3/8161.44 / 1.310.79 / 0.650.24 / 0.200.70 / 0.640.30 / 0.26A 36.6 mm, B 20.1 mm

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

CDE FastenersWing screws type A, cold formed (sheet cites ASME B18.6.8-2010): wing spread A, height B, thickness C, boss E and G max / min, sizes 8 to 3/8webMaker datasheet; numbers only
Tanner Bolt (wing nut sheet, ASME B18.17)Cold-forged wing nuts: A, B, C, D, E, G (cross-check of the shared wing and boss dimensions)webMaker datasheet; numbers only
McMaster-CarrWing screws (category)web, STEPMcMaster-Carr site terms: personal design use, no redistribution verify

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Plain text: sheet.txt · JSON: /api/geometry?object=wing-screws-inch-asme-b18-17

length
Schematic, not to scale.

Fits with

length
Wing screws, DIN 316 (round wings, German form), M4–M24: boss, wing span, height and nominal lengths9 sizes★ sheet
length
Wing nuts: DIN 315 M4–M24 and ASME B18.17 #4 to 3/4 — boss, wing spread, height, wing thickness31 sizes★ sheet
Knurled thumb screws, low type (DIN 653), M1–M10: head diameter, head height, shank, nominal lengths + 6 models, isometric render of a generated part
Knurled thumb screws, low type (DIN 653), M1–M10: head diameter, head height, shank, nominal lengths + 6 models36.0×36.0×28.0 mm★ 6 files
Knurled thumb screws, high type (DIN 464), M2–M10: head diameter, head height, shank, thread length, slot8 sizes★ sheet
Imperial machine screws: #4-40, #6-32, #8-32, 1/4-20, isometric render of a generated part
Imperial machine screws: #4-40, #6-32, #8-32, 1/4-204 sizes★ 18 files
length
Star knobs, DIN 6336 (cast iron), Ø32–80: thread, bore, height and depth5 sizes★ sheet

Questions

How wide is a 1/4-20 wing screw?

Wing spread A is 1.10 in max / 0.97 in min (27.9 / 24.6 mm), wing height B 0.57 / 0.43 in (CDE sheet).

What are the boss dimensions of a #10 wing screw?

Boss E 0.43 / 0.39 in, boss height G 0.18 / 0.14 in.

Are wing screws and wing nuts the same wing size?

Yes for the shared sizes: A, B, C, E and G match between CDE's wing screw sheet and Tanner's ASME B18.17 wing nut sheet.