Table 2: Allowable Pin and Tap Size Combinations
(dimensions in inches)

Tap Size ‘U’	Pin Diameter ‘P’
	1/2	5/8	3/4	7/8	1	1-1/4	1-1/2	1-3/4	2	2-1/4	2-1/2	2-3/4	3	3-1/4	3-1/2
3/8	2	2	2
1/2	2	2	2
5/8	2	2	2	2-1/2	2-1/2	2-1/2	2-1/2
3/4			2-1/2	2-1/2	2-1/2	2-1/2	2-1/2
7/8				2-1/2	2-1/2	2-1/2	2-1/2	3
1					3	3	3	3
1-1/8					3	3	3	3	3-1/2
1-1/4					3	3	3	3	3-1/2
1-3/8					3	3	3	3-1/2	3-1/2	4
1-1/2						3-1/2	3-1/2	4	4	5
1-5/8						4	4	4	5	5	5
1-3/4						4	4	5	5	5	5
1-7/8							5	5	5	5	5
2							5	5	5	5	5	6	6
2-1/4									6	6	6	6	6	7	7
2-1/2									6	6	6	7	7	7	7
2-3/4											7	7	7	7
2-3/4											7

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