Button head socket cap screws, inch: #4-40 to 1/2-13 (ASME B18.3) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/button-head-socket-screws-inch/  (CC BY 4.0)
Basis: ASME B18.3 inch socket screws: head diameter A (max), head height H, hex socket J; thread drawn as a plain cylinder at the major diameter
Catalog version: 2026-10-20

Sizes: see table below
- The low-profile screw T-slot framing uses on brackets and panels: 1/4-20 for 10-series, 5/16-18 for 15-series. Length is under the head; the head is a dome to height H over diameter A.

size  major_mm  tpi  head_dia_mm  head_h_mm  hex_key_in  lengths_in
#4-40  2.845  40  5.41  1.5  1/16  0.25, 0.375, 0.5
#6-32  3.505  32  6.65  1.83  5/64  0.25, 0.375, 0.5
#8-32  4.166  32  7.92  2.11  3/32  0.375, 0.5
#10-24  4.826  24  9.17  2.54  1/8  0.375, 0.5, 0.75
#10-32  4.826  32  9.17  2.54  1/8  0.375, 0.5
1/4-20  6.35  20  11.1  3.35  5/32  0.375, 0.5, 0.625, 0.75, 1
5/16-18  7.938  18  13.89  4.22  3/16  0.5, 0.625, 0.75, 1
3/8-16  9.525  16  16.66  5.05  7/32  0.75, 1
1/2-13  12.7  13  22.22  6.73  5/16  1

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- ASME: B18.3 Socket cap, shoulder, set screws, hex and spline keys (inch series): head diameter, height, hex socket — standard — ASME; dimensions are facts [verify license at link] — https://www.asme.org/codes-standards/find-codes-standards/b18-3-socket-cap-shoulder-set-screws-hex-spline-keys-inch-series

Free files (CC BY 4.0, Xem Studio; STEP + STL, 25 parts): https://xemstudio.com/files/hardware/button-head-socket-screws-inch/index.json
API: https://xemstudio.com/api/geometry?object=button-head-socket-screws-inch