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THREAD DATA CHARTS

UNC Thread ANSI B1.1

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UNC Thread ANSI B1.1
UNC - Unified Coarse Thread. The old definition NC - National Coarse is comparable with the metric thread. The new term UNC is comparable with the ISO metric thread. NC and UNC threads are interchangeable, in an similar manner to the metric and the ISO metric thread.
Nominal	Major	Major	Tapping	TPI	Pitch
Diameter	Diameter	Diameter	Drill Size		mm
	Inch	mm	mm
1 - 64 UNC	0,073	1,854	1,50	64	0,397
2 - 56 UNC	0,086	2,184	1,80	56	0,453
3 - 48 UNC	0,099	2,515	2,10	48	0,529
4 - 40 UNC	0,112	2,845	2,35	40	0,635
5 - 40 UNC	0,125	3,175	2,65	40	0,635
6 - 32 UNC	0,138	3,505	2,85	32	0,794
8 - 32 UNC	0,164	4,166	3,50	32	0,794
10 - 24 UNC	0,190	4,826	4,00	24	1,058
12 - 24 UNC	0,216	5,486	4,65	24	1,058
1/4" - 20 UNC	0,250	6,350	5,35	20	1,270
5/16" - 18 UNC	0,313	7,938	6,80	18	1,411
3/8" - 16 UNC	0,375	9,525	8,25	16	1,587
7/16" - 14 UNC	0,438	11,112	9,65	14	1,814
1/2" - 13 UNC	0,500	12,700	11,15	13	1,954
9/16" - 12 UNC	0,563	14,288	12,60	12	2,117
5/8" - 11 UNC	0,625	15,875	14,05	11	2,309
3/4" - 10 UNC	0,750	19,050	17,00	10	2,540
7/8" - 9 UNC	0,875	22,225	20,00	9	2,822
1" - 8 UNC	1,000	25,400	22,85	8	3,175
1 1/8" - 7 UNC	1,125	28,575	25,65	7	3,628
1 1/4" - 7 UNC	1,250	31,750	28,85	7	3,628
1 3/8" - 6 UNC	1,375	43,925	31,55	6	4,233
1 1/2" - 6 UNC	1,500	38,100	34,70	6	4,233
1 3/4" - 5 UNC	1,750	44,450	40,40	5	5,080
2" - 4 1/2 UNC	2,000	50,800	46,30	4,5	5,644
2 1/4" - 4 1/2 UNC	2,250	57,150	52,65	4,5	5,644
2 1/2" - 4 UNC	2,500	63,500	58,50	4	6,350
2 3/4" - 4 UNC	2,750	69,850	64,75	4	6,350
3" - 4 UNC	3,000	63,500	71,10	4	6,350
3 1/4" - 4 UNC	3,250	82,550	77,45	4	6,350
3 1/2" - 4 UNC	3,500	88,900	83,80	4	6,350
3 3/4" - 4 UNC	3,750	95,250	90,15	4	6,350
4" - 4 UNC	4,000	101,600	96,50	4	6,350
UNC Thread

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