Side-by-Side Comparison
Imperial Threads (UNC/UNF)
#10-24 UNC vs. #8-32 UNC
Comparing 2 standards across 9 specifications. 9 key differences identified.
Comparing:
#10-24 UNC
#8-32 UNC
10-24 UNC is a numbered Unified Coarse machine screw thread with a major diameter of 0.1900 inches (4.826 mm) and 24 threads per inch (TPI). Requiring a #25 (0.1495 inch) tap drill, it provides high clamping torque for household appliances, outdoor power equipment, and light mechanical assemblies.
8-32 UNC is a numbered Unified Coarse machine screw thread with a major diameter of 0.1640 inches (4.166 mm) and 32 threads per inch (TPI). Requiring a #29 (0.1360 inch) tap drill, it is the standard fastener for North American electrical ceiling junction boxes, light fixtures, and kitchen cabinet hardware knobs.
Specification Comparison Table
9 Parameters| Parameter / Spec | ||
|---|---|---|
|
Nominal Major Diameter
|
0.1900 in (4.826 mm) | 0.1640 in (4.166 mm) |
|
Threads Per Inch (TPI)
|
24 TPI (Coarse pitch: 1.058 mm) | 32 TPI (Coarse pitch: 0.794 mm) |
|
Fine Pitch Equivalent
|
#10-32 UNF (0.794 mm pitch — widely used in 19" AV racks) | #8-36 UNF (0.706 mm pitch) |
|
Minor Diameter (Internal)
|
0.1449 in (3.680 mm) | 0.1302 in (3.307 mm) |
|
Tensile Stress Area
|
0.0175 in² (11.3 mm²) | 0.0140 in² (9.03 mm²) |
|
Tap Drill Size (UNC)
|
#25 drill bit (0.1495 in / 3.80 mm) | — |
|
Tap Drill Size (#10-32 UNF)
|
#21 drill bit (0.1590 in / 4.04 mm) | — |
|
Recommended Tap Drill Size
|
— | #29 drill bit (0.1360 in / 3.45 mm) |
|
Common Drive Size
|
— | PH2 / Slotted / Square #2 |