UNC coarse thread chart

27 sizes · ThreadRef · sample of the first 8 rows

UNC coarse thread chart. The Unified coarse series, #0 to 2-1/2 inch: threads per inch, major, pitch and minor diameters, the tap drill in both inches and millimetres, and the hex across-flats.
Size	TPI	Major dia in	Pitch dia in	Minor dia in	Tap drill in	Tap drill mm	Hex A/F
#1-64 UNC	64	0.073	0.0629	0.0561	0.0595	1.51	not defined
#2-56 UNC	56	0.086	0.0744	0.0667	0.07	1.78	not defined
#3-48 UNC	48	0.099	0.0855	0.0764	0.0785	1.99	not defined
#4-40 UNC	40	0.112	0.0958	0.0849	0.089	2.26	not defined
#5-40 UNC	40	0.125	0.1088	0.0979	0.1015	2.58	not defined
#6-32 UNC	32	0.138	0.1177	0.1042	0.1065	2.71	not defined
#8-32 UNC	32	0.164	0.1437	0.1302	0.136	3.45	not defined
#10-24 UNC	24	0.19	0.1629	0.1449	0.1495	3.8	not defined

Dimensions per ASME B1.1 (Unified inch screw threads); wrench sizes per ASME B18.2.1.

Torque figures are estimates that depend on the stated nut-factor assumption. Verify against your fastener manufacturer's data and joint requirements before assembly.

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