Threading: Standard Holes

UNC, UNF, and metric threads are available for standard holes on both milled and turned parts.

UNC threads	Minimum modeled diameter (in.)	Maximum modeled diameter (in.)	75% hole drill size (in.)	Maximum thread depth (in.)*
#2-56	0.067	0.074	0.070	0.200
#3-48	0.076	0.084	0.082	0.200
#4-40	0.085	0.094	0.089	0.300
#5-40	0.098	0.104	0.102	0.300
#6-32	0.105	0.114	0.109	0.400
#8-32	0.130	0.139	0.134	0.400
#10-24	0.145	0.156	0.150	0.600
#12-24	0.171	0.181	0.176	0.600
1/4-20	0.196	0.207	0.201	0.650
5/16-18	0.252	0.265	0.259	0.650
3/8-16	0.307	0.321	0.314	1.000
7/16-14	0.360	0.376	0.372	1.000
1/2-13	0.417	0.434	0.426	1.200

*Obstruction by other features of your part, lead-in treatments, or fixturing requirements may reduce the maximum depth of threads.

UNF threads	Minimum modeled diameter (in.)	Maximum modeled diameter (in.)	75% hole drill size (in.)	Maximum thread depth (in.)*
#2-64	0.069	0.075	0.072	0.200
#3-56	0.080	0.084	0.083	0.200
#4-48	0.087	0.098	0.093	0.300
#5-44	0.100	0.104	0.104	0.300
#6-40	0.111	0.119	0.115	0.400
#8-36	0.134	0.142	0.138	0.400
#10-32	0.156	0.164	0.160	0.600
#12-28	0.177	0.186	0.182	0.600
1/4-28	0.211	0.220	0.215	0.650
5/16-24	0.267	0.277	0.272	0.650
3/8-24	0.330	0.340	0.335	1.000
7/16-20	0.383	0.395	0.389	1.000
1/2-20	0.446	0.457	0.451	1.200

*Obstruction by other features of your part, lead-in treatments, or fixturing requirements may reduce the maximum depth of threads.

Metric threads	Minimum modeled diameter (mm)	Maximum modeled diameter (mm)	75% hole drill size (mm)	Maximum thread depth (mm)*
M1.6 x 0.35**	1.22	1.32	1.25	3
M2 x 0.4	1.57	1.68	1.60	5.08
M2.5 x 0.45	2.01	2.14	2.05	5.08
M3 x 0.5	2.46	2.60	2.50	7.62
M3.5 x 0.6	2.85	3.01	2.90	10.16
M4 x 0.7	3.24	3.42	3.30	10.16
M5 x 0.8	4.14	4.33	4.20	15.24
M6 x 1.0	4.92	5.15	5.00	16.51
M8 x 1.25	6.65	6.91	6.80	16.51
M10 x 1.5	8.38	8.68	8.50	25.40
M12 x 1.75	10.00	10.44	10.20	30.48

*Obstruction by other features of your part, lead-in treatments, or fixturing requirements may reduce the maximum depth of threads.

**Aluminum Only

UNC threads	Minimum modeled diameter (in.)	Maximum modeled diameter (in.)	75% hole drill size (in.)	Maximum thread depth (in.)
#4-40	0.085	0.094	0.089	0.300
#5-40	0.098	0.106	0.102	0.300
#6-32	0.105	0.114	0.109	0.400
#8-32	0.130	0.139	0.134	0.400
#12-24*	0.171	0.181	0.176	0.500
1/4-20*	0.196	0.207	0.201	0.500

*Threads must be centered on the axis of rotation

UNF threads	Minimum modeled diameter (in.)	Maximum modeled diameter (in.)	75% hole drill size (in.)	Maximum thread depth (in.)
#4-48	0.087	0.098	0.093	0.300
#5-44	0.100	0.108	0.104	0.300
#6-40	0.111	0.119	0.115	0.400
#8-36	0.134	0.142	0.138	0.400
#10-32	0.156	0.164	0.160	0.400
#12-28*	0.177	0.186	0.182	0.500
1/4-28*	0.211	0.220	0.215	0.500
5/16-24*	0.267	0.277	0.272	0.500
3/8-24*	0.330	0.340	0.335	0.500
7/16-20*	0.383	0.395	0.389	0.500
1/2-20*	0.446	0.457	0.451	0.500

*Threads must be centered on the axis of rotation

Metric threads	Minimum modeled diameter (mm)	Maximum modeled diameter (mm)	75% hole drill size (mm)	Maximum thread depth (mm)
M3 x 0.5	2.46	2.60	2.50	7.62
M3.5 x 0.6	2.85	3.01	2.90	10.16
M4 x 0.7	3.24	3.42	3.30	10.16
M5 x 0.8	4.14	4.33	4.20	10.16
M6 x 1.0*	4.92	5.15	5.00	12.70
M8 x 1.25*	6.65	6.91	6.80	12.70
M8 x 1.0*	6.91	7.16	7.01	12.70
M10 x 1.25*	8.64	8.92	8.79	12.70

*Threads must be centered on the axis of rotation