Xem Studiomeasured geometryLibrary › Hardware › Imperial machine screws: #4-40, #6-32, #8-32, 1/4-20
1/4-20 SHCS × 1/2 in (12.7 mm), head Ø9.525 × 6.35, thread as Ø6.35 plain cylinder
1/4-20 SHCS × 1/2 in (12.7 mm), head Ø9.525 × 6.35, thread as Ø6.35 plain cylinder
Exact dimensions. True size, no printing tolerance added. Threads are plain cylinders at the major diameter.
STEP STL free, CC BY 4.0 (credit "Xem Studio")
Dimensions
| size | 1/4-20 |
|---|---|
| major_mm | 6.35 |
| tpi | 20 |
| clearance_mm | 6.8 |
| tap_drill_mm | 5.11 |
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Imperial machine screws: #4-40, #6-32, #8-32, 1/4-20: every size, notes, mating features and sources. What are the clearance and tap drill sizes for #4-40, #6-32, #8-32 and 1/4-20?
Other sizes
- #4-40 SHCS × 1/4 in (6.35 mm), head Ø4.648 × 2.845, thread as Ø2.845 plain cylinder
- #4-40 SHCS × 3/8 in (9.525 mm), head Ø4.648 × 2.845, thread as Ø2.845 plain cylinder
- #4-40 SHCS × 1/2 in (12.7 mm), head Ø4.648 × 2.845, thread as Ø2.845 plain cylinder
- #4-40 SHCS × 3/4 in (19.05 mm), head Ø4.648 × 2.845, thread as Ø2.845 plain cylinder
- #6-32 SHCS × 1/4 in (6.35 mm), head Ø5.74 × 3.505, thread as Ø3.505 plain cylinder
- #6-32 SHCS × 3/8 in (9.525 mm), head Ø5.74 × 3.505, thread as Ø3.505 plain cylinder
- #6-32 SHCS × 1/2 in (12.7 mm), head Ø5.74 × 3.505, thread as Ø3.505 plain cylinder
- #6-32 SHCS × 3/4 in (19.05 mm), head Ø5.74 × 3.505, thread as Ø3.505 plain cylinder
- #6-32 SHCS × 1 in (25.4 mm), head Ø5.74 × 3.505, thread as Ø3.505 plain cylinder
- #8-32 SHCS × 3/8 in (9.525 mm), head Ø6.858 × 4.166, thread as Ø4.166 plain cylinder
- #8-32 SHCS × 1/2 in (12.7 mm), head Ø6.858 × 4.166, thread as Ø4.166 plain cylinder
- #8-32 SHCS × 3/4 in (19.05 mm), head Ø6.858 × 4.166, thread as Ø4.166 plain cylinder
- #8-32 SHCS × 1 in (25.4 mm), head Ø6.858 × 4.166, thread as Ø4.166 plain cylinder
- 1/4-20 SHCS × 3/4 in (19.05 mm), head Ø9.525 × 6.35, thread as Ø6.35 plain cylinder
- 1/4-20 SHCS × 1 in (25.4 mm), head Ø9.525 × 6.35, thread as Ø6.35 plain cylinder
- 1/4-20 SHCS × 1-1/4 in (31.75 mm), head Ø9.525 × 6.35, thread as Ø6.35 plain cylinder
- 1/4-20 SHCS × 1-1/2 in (38.1 mm), head Ø9.525 × 6.35, thread as Ø6.35 plain cylinder