Product Detail 25: Widia Tap, #8-32 UNC H3 ANSI 4FL Taper Hand HSS (15283) .

UNC Pipe Tap Size (in)	UNC				UNF Pipe Tap Size (in)	UNF
	Pitch (TPI)	Drill Size (in)	Drill Size (in)			Pitch (TPI)	Drill Size (in)	Drill Size (in)
8-32	32	#29	0.1360		8-36	36	#29	0.1360
10-24	24	#25	0.1495		10-32	32	#21	0.1590
12-24	24	#16	0.1770		12-28	28	#15	0.1800
1/4-20	20	#7	0.2010		1/4-28	28	#3	0.2130
5/16-18	18	F	0.2570		5/16-24	24	I	0.2720
3/8-16	16	5/16	0.3125		3/8-24	24	Q	0.3320
7/16-14	14	U	0.3680		7/16-20	20	27/64	0.4219
1/2-13	13	27/64	0.4219		1/2-20	20	29/64	0.4531
9/16-12	12	31/64	0.4844		9/16-18	18	33/64	0.5156
5/8-11	11	17/32	0.5313		5/8-18	18	37/64	0.5781
3/4-10	10	21/32	0.6563		3/4-16	16	11/16	0.6875
7/8-9	9	49/64	0.7656		7/8-14	14	13/16	0.8125
1-8	8	7/8	0.8750		1-12	12	59/64	0.9219
1-1/8-7	7	63/64	0.9844		1-1/8-12	12	1-3/64	1.0469
1-1/4-7	7	1-7/64	1.1094		1-1/4-12	12	1-11/64	1.1719
1-3/8-6	6	1-13/64	1.2031		1-3/8-12	12	1-19/64	1.2969
1-1/2-6	6	1-11/32	1.3438		1-1/2-12	12	1-27/64	1.4219
1-3/4-5	5	1-35/64	1.5469		N/A
2-4.5	4.5	1-25/32	1.7813

2020-06-22

Objective:

Manafactured by Wadia:

2020-06-16 Retailer: McMaster PN 2522A668; Wadia Tap #8-32 UNC H3 ANSI 4FL Taper Hand HSS Tap; Cost $5.07.

2020-07-10 Retailer: McMaster PN 2626A42; Wadia Tap #3/8-24 UNF H3 ANSI 3FL PLG RHSF NI/OX; Cost $34.90. For nickel, closed end.

2020-07-10 Retailer: McMaster PN 27055A47; Wadia Tap #3/8-24 UNF H3 ANSI 3FL SBOT RHSF HSSE OX; Cost $23.38. For Steel and SS, closed end.

The WIDI closed end taps have a tip taper length of 2 - 2.5 threads, this was too long from my application. I found EXO 3/8 24 UNF insert that was better suited for close-end holes. Cost was also about $30 USD.