Pipe thread drill sizes
	Tap Drill Size
	NPT (taper)		NPS (straight)
Thread size	Inches	MM	Inches	MM
1/8 - 27	Q	8.5	11/32	8.75
1/4 - 18	7/16	11	7/16	11.5
3/8 - 18	9/16	14.5	31/64	15
1/2 - 14	45/64	18	23/32	18.5
3/4 - 14	29/32	23	25/32	23.5
1 - 11 1/2	1 9/64	29	1 5/32	29.5
1 1/4 - 11 1/2	1 31/64	38	1 1/2	38.5
1 1/2 - 11 1/2	1 47/64	44	1 3/4	44.5
2 - 11 1/2	2.13/64	56	2 7/32	57
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www.powerbyace.com
				5/23/2009
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