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UNIFIED MINIATURE SCREW THREADS

(All dimensions in inches)**
BASIC DIAMETERS
Size Designation Preferred*		0.30UNM		0.40UNM		0.50UNM		0.60UNM
Size Designation Preferred*			0.35UNM		0.45UNM		0.55UNM
Basic Major Diameter-D		0.0118	0.0138	0.0157	0.0177	0.0197	0.0217	0.0236
Basic Pitch Diameter-E		0.0098	0.0115	0.0132	0.0152	0.0165	0.0185	0.0198
Basic Minor Diameter-K		0.0085	0.0101	0.0117	0.0136	0.0146	0.0165	0.0175
Threads Per inch		318	282	254	254	203	203	169
Lead Angle at Basic P.D - (l)		5° 52'	5° 37'	5° 26'	4° 44'	5° 26'	4° 51'	5° 26'
EXTERNAL THREADS
Major Diameter	Max.Min.	0.01180.0112	0.01380.0131	0.01570.0150	0.01770.0170	0.01970.0189	0.02170.0208	0.02360.0227
Pitch Diameter	Max.Min.	0.00980.0092	0.01150.0109	0.01320.0126	0.01520.0145	0.01650.0158	0.01850.0177	0.01980.0190
Minor Diameter	Max.Min.	0.00800.0072	0.00950.0086	0.01100.0101	0.01300.0120	0.01380.0127	0.01570.0146	0.01650.0153
INTERNAL THREADS
Minor Diameter	Max.Min.	0.01000.0085	0.01170.0101	0.01340.0117	0.01540.0136	0.01660.0146	0.01860.0165	0.01980.0175
Pitch Diameter	Max.Min.	0.01040.0098	0.01210.0115	0.01380.0132	0.01580.0152	0.01720.0165	0.01920.0185	0.02060.0198
Major Diameter	Max.Min.	0.01290.0120	0.01490.0140	0.01700.0160	0.01900.0180	0.02120.0200	0.02310.0220	0.02540.0240
HOLE SIZES BEFORE TAPPING / LENGTH OF ENGAGEMENT
2/3D	Max.Min.	0.00950.0089	0.01110.0105	0.01270.0121	0.01470.0141	0.01580.0150	0.01780.0170	0.01900.0181
2/3 - 1-1/2D	Max.Min.	0.01000.0093	0.01170.0109	0.01340.0125	0.01540.0145	0.01660.0156	0.01860.0176	0.01980.0187
1-1/2 - 3D***	Max.Min.	0.01040.0096	0.01210.0113	0.01380.0130	0.01580.0149	0.01710.0161	0.01910.0181	0.02040.0193

BASIC DIAMETERS
Size Designation Preferred*			0.80UNM		1.00UNM		1.20UNM
Size Designation Preferred*		0.70UNM		0.90UNM		1.10UNM		1.40UNM
Basic Major Diameter-D		0.0276	0.0315	0.0354	0.0394	0.0433	0.0472	0.0551
Basic Pitch Diameter-E		0.0231	0.0264	0.0297	0,0330	0.0369	0.0409	0.0474
Basic Minor Diameter-K		0.0204	0.0233	0.0262	0.0291	0.0331	0.0370	00.0428
Threads Per inch		145	127	113	102	102	102	85
Lead Angle at Basic P.D - (l)		5° 26'	5° 26'	5° 26'	5° 26'	4° 51'	4° 23'	4° 32'
EXTERNAL THREADS
Major Diameter	Max.Min.	0.02760.0265	0.03150.0303	0.03540.0341	0.03940.0380	0.04330.0419	0.04720.0458	0.05510.0535
Pitch Diameter	Max.Min.	0.02310.0222	0.02640.0254	0.02970.0287	0.03300.0319	0.03690.0358	0.04090.0.397	0.04740.0462
Minor Diameter	Max.Min.	0.01930.0179	0.02200.0205	0.02480.0231	0.02760.0257	0.03150.0296	0.03540.0335	0.04090.0387
INTERNAL THREADS
Minor Diameter	Max.Min.	0.02310.0204	0.02630.0233	0.02950.0262	0.03270.0291	0.03670.0331	0.04060.0370	0.04710.0428
Pitch Diameter	Max.Min.	0.02400.0231	0.02730.0264	0.03070.0297	0.03410.0330	0.03800.0369	0.04200.0409	0.04870.0474
Major Diameter	Max.Min.	0.02950.0281	0.03370.0321	0.03790.0361	0.04200.0401	0.04600.0440	0.04990.0480	0.05830.0560
HOLE SIZES BEFORE TAPPING / LENGTH OF ENGAGEMENT
2/3D	Max.Min.	0.02210.0211	0.02520.0241	0.02830.0270	0.03140.0300	0.03540.0340	0.03930.0379	0.04550.0439
2/3 - 1-1/2D	Max.Min.	0.02310.0217	0.02630.0248	0.02950.0279	0.03270.0309	0.03670.0349	0.04060.0388	0.04710.0450
1-1/2 - 3D***	Max.Min.	0.02370.0224	0.02700.0256	0.03040.0287	0.03370.0319	0.03760.0358	0.04150.0397	0.04810.0460

*It is recommended that selections be confined to preferred sizes insofar as possible.
**ASA Standard B1, 19-1958 also lists metric equivelents which are interchangeable in assembly with inches.
***It is not recommended that holes deeper than 3D be used. In tougher materials, use shallowest holes possible.
****For reference only, not gaged. Use max. diameter of external thread as min. gage O.D.

MINIATURE SCREWS

(All dimensions in inches)**
Fillister Head
Size Designation	Preferred*	.30UNM		.40UNM		.50UNM		.60UNM
Size Designation			.35UNM		.45UNM		.55UNM
Head Diameter - A	Max. Min.	0.021 0.019	0.023 0..021	0.025 0.023	0.029 0.027	0.033 0.031	0.037 0.035	0.041 0.039
Head Height - H	Max. Min.	0.012 0.010	0.014 0.012	0.016 0.013	0.018 0.015	0.020 0.017	0.022 0.019	0.025 0.021
Slot Width - J	Max. Min.	0.004 0.003	0.004 0.003	0.005 0.003	0.005 0.003	0.006 0.004	0.006 0.004	0.008 0.005
Slot Depth - T(a)	Max Min.	0.006 0.004	0.007 0.005	0.008 0.006	0.009 0.007	0.010 0.007	0.011 0.008	0.012 0.009
Chamfer - C	Max.	0.002	0.002	0.002	0.002	0.003	0.003	0.004
Radius - R(b)	Max.	0.002	0.002	0.002	0.002	0.002	0.002	0.003

Size Designation	Preferred*		.80UNM		1.00UNM		1.20UNM
Size Designation		.70UNM		.90UNM		1.10UNM		1.40UNM
Head Diameter - A	Max. Min.	0.045 0.043	0.051 0.049	0.056 0.054	0.062 0.058	0.072 0.068	0.082 0.078	0.092 0.088
Head Height - H	Max. Min.	0.028 0.024	0.032 0.028	0.036 0.032	0.040 0.035	0.045 0.040	0.050 0.045	0.055 0.050
Slot Width - J	Max. Min.	0.008 0.005	0.010 0.007	0.010 0.007	0.012 0.008	0.012 0.008	0.016 0.012	0.016 0.012
Slot Depth - T(a)	Max Min.	0.014 0.011	0.016 0.012	0.020 0.016	0.020 0.016	0.022 0.018	0.025 0.020	0.028 0.023
Chamfer - C	Max.	0.004	0.005	0.005	0.006	0.006	0.008	0.008
Radius - R(b)	Max.	0.003	0.004	0.004	0.005	00.005	00.006	0.006

Pan Head
Size Designation	Preferred*	.30UNM		.40UNM		.50UNM		.60UNM
Size Designation			.35UNM		.45UNM		.55UNM
Head Diameter - A	Max. Min.	0.025 0.023	0.029 0.027	0.033 0.031	0.037 0.035	0.041 0.039	0.045 0.043	0.051 0.049
Head Height - H	Max. Min.	0.010 0.008	0.011 0.009	0.012 0.010	0.014 0.012	0.016 0.013	0.018 0.015	0.020 0.017
Slot Width - J	Max. Min.	0.005 0.003	0.005 0.003	0.006 0.004	0.006 0.004	0.008 0.005	0.008 0.005	0.010 0.007
Slot Depth - T(a)	Max Min.	0.005 0.003	0.006 0.004	0.006 0.004	0.007 0.005	0.008 0.006	0.009 0.007	0.010 0.007
Chamfer - C	Max.	0.002	0.002	0.002	0.002	0.003	0.003	0.004
Radius - R(b)	Max.	0.002	0.002	0.002	0.002	0.002	0.002	0.003

Size Designation	Preferred*		.80UNM		1.00UNM		1.20UNM
Size Designation		.70UNM		.90UNM		1.10UNM		1.40UNM
Head Diameter - A	Max. Min.	0.056 0.054	0.062 0.058	0.072 0.068	0.082 0.088	0.092 0.088	0.103 0.097	0.113 0.107
Head Height - H	Max. Min.	0.022 0.019	0.025 0.021	0.028 0.024	0.032 0.028	0.036 0.032	0.040 0.035	0.045 0.040
Slot Width - J	Max. Min.	0.010 0.007	0.012 0.008	0.012 0.008	0.016 0.012	0.016 0.012	0.020 0.015	0.020 0.015
Slot Depth - T(a)	Max Min.	0.011 0.008	0.012 0.009	0.014 0.011	0.018 0.014	0.018 0.014	0.020 0.016	0.022 0.018
Chamfer - C	Max.	0.004	0.005	0.005	0.006	0.006	0.008	0.008
Radius - R(b)	Max.	0.003	0.004	0.004	0.005	00.005	00.006	0.006

Flat Head (100 DSEG.)
Size Designation	Preferred*	.30UNM		.40UNM		.50UNM		.60UNM
Size Designation			.35UNM		.45UNM		.55UNM
Head Diameter - A	Max. Min.	0.023 0.021	0.025 0.023	0.029 0.027	0.033 0.031	0.037 0.035	0.041 0.039	0.045 0.043
AV. DIA. at MAX - H		0.0285	0.0305	0.0348	0.0392	0.0459	0.0503	0.0546
Head Height - H	Max. Min.	0.007 0.005	0.007 0.005	0.008 0.006	0.009 0.007	0.011 0.008	0.012 0.009	0.013 0.010
Slot Width - J	Max. Min.	0.004 0.003	0.004 0.003	0.005 0.003	0.005 0.003	0.006 0.004	0.006 0.004	0.008 0.005
Slot Depth - T	Max. Min.	0.004 0.002	0.004 0.002	0.005 0.003	0.005 0.003	0.006 0.004	0.006 0.004	0.008 0.005
Radius - R(b)	Max.	0.005	0.005	0.006	0.006	0.008	0.008	0.010

Size Designation	Preferred*		.80UNM		1.00UNM		1.20UNM
Size Designation		.70UNM		.90UNM		1.10UNM		1.40UNM
Head Diameter - A	Max. Min.	0.051 0.049	0.056 0.054	0.062 0.058	0.072 0.068	0.082 0.078	0.092 0.088	0.0103 0.097
AV. DIA. at MAX - H		0.0610	0.0696	0.0759	0.0847	0.0957	0.1068	0.1197
Head Height - H	Max. Min.	0.014 0.011	0.016 0.012	0.017 0.013	0.019 0.015	0.022 0.018	0.025 0.020	0.027 0.022
Slot Width - J	Max. Min.	0.008 0.005	0.010 0.007	0.010 0.007	0.012 0.008	0.012 0.008	0.016 0.012	0.016 0.012
Slot Depth - T	Max. Min.	0.008 0.005	0.010 0.006	0.010 0.006	0.012 0.008	0.012 0.008	0.016 0.010	0.016 0.010
Radius - R(b)	Max.	0.010	0.012	0.012	0.016	0.016	0.020	0.020

* It is recommended that selections be confined to preferred sizes insofar as possible.
** ASA Standard Be.10-1958 also lists metric equivelents which are interchangeable is assembly with inches.
(a) Slot Depth "T" measured from bearing surface.
(b) Radius "R" relative to max. major dia.
There is no standard for nuts available or under consideration at the present time.

**STANDARD LENGTHS^(c)**
Length	(In.)	(d).30UNM*	.35UNM*	.40UNM	.45UNM	.50UNM	.55UNM	.60UNM	.70UNM	.80UNM	.90UNM	1.00UNM	1.10UNM	1.20UNM	1.40UNM
Max.	Min.	(e) (0.0118)	(0.0138)	(0.0157)	(0.0177)	(0.0197)	(0.0217)	(0.0236)	(0.0276)	(0.0315)	(0.0354)	(0.0394)	(0.0433)	(0.0472)	(0.0551)
0.020	0.016	30-020
0.025	0.021	30-025	35-025	40-025
0.032	0.027	30-032	35-032	40-032	45-032	50-032
0.040	0.035	30-040	35-040	40-040	45-040	50-040	55-040	60-040
0.050	0.044	30-050	35-050	40-050	45-050	50-050	55-050	60-050	70-050	80-050
0.060	0.054	30-060	35-060	40-060	45-060	50-060	55-060	60-060	70-060	80-060	90-060	100-060
0.080	0.072	30-080	35-080	40-080	45-080	50-080	55-080	60-080	70-080	80-080	90-080	100-080	110-080	120-080
0.100	0.092	30-100	35-100	40-100	45-100	50-100	55-100	60-100	70-100	80-100	90-100	100-100	110-100	120-100	140-100
0.120	0.110	30-120	35-120	40-120	45-120	50-120	55-120	60-120	70-120	80-120	90-120	100-120	110-120	120-120	140-120
0.160	0.150	30-160	35-160	40-160	45-160	50-160	55-160	60-160	70-160	80-160	90-160	100-160	110-160	120-160	140-160
0.200	0.188		35-200	40-200	45-200	50-200	55-200	60-200	70-200	80-200	90-200	100-200	110-200	120-200	140-200
0.250	0.238				45-250	50-250	55-250	60-250	70-250	80-250	90-250	100-250	110-250	120-250	140-250
0.320	0.304						55-320	60-320	70-320	80-320	90-320	100-320	110-320	120-320	140-320
0.400	0.384								70-400	80-400	90-400	100-400	110-400	120-400	140-400
0.500	0.480										90-500	100-500	110-500	120-500	140-500
0.600	0.580												110-600	120-600	140-600

(c) Bold face type indicates preferred sizes. (d) Size Designation (e) Basic Major Diam.
Standard lengths in all sizes are available in Fillister, Pan 100° Flat and Binding Heads with the following exceptions:
*BINDING HEADS HAVE NO STANDARD LENGTHS IN 30 LAND 35 UNM

Mauve Shading
Figures in this area are standard only for Fillister, Pan
and Binding (except 30 & 35 UNM Binding) Heads.
Not standard for 100° Flat.

GREEN FIGURES
(30-160, etc.)
Standard for 100° Flat Head only.

Above lengths are considered standard only and do not imply stock availability from J.I. Morris Co.

HEAD	Size			00-112
HEAD	Size			00-96		1-64	2-64
HEAD	Size	0000-160	000-120	00-90	0-80	1-72	2-56
HEAD	Body dia. (D)	.021	.034	.047	.060	.073	.086
HEX	Hd. Dia. (across flats (A)	3/64"	5/64"	5/64"	3/32"	7/64"	1/8"
HEX	Head Height (H)	.025	.033	.042	.042	.055	.064
ROUND	Head Dia. (A)	.038	.059	.085	.106	.130	.154
ROUND	Head Height (H)	.019	.028	.041	.047	.055	.065
ROUND	Slot Width	.006	.010	.013	.019	.022	.028
ROUND	Slot Depth	.010	.015	.022	.032	.037	.042
FLAT	Head Dia. (A)	.040	.061	.089	.108	.136	.164
FLAT	Head Height (H) (normal)	.011	.016	.024	.035	.043	.051
FLAT	Slot Width	.006	.009	.013	.019	.022	.028
FLAT	Slot Depth	.005	.007	.010	.013	.016	.019
OVAL FILL	Head Dia. (A)	.035	.056	.078	.091	.111	.132
OVAL FILL	Head height FE	.019	.031	.043	.051	.062	.073
OVAL FILL	Slot Width	.006	.009	.013	.019	.022	.027
OVAL FILL	Slot Depth	.009	.014	.019	.022	.025	.029
NUT	Across Flats (A)	3/64"	5/64"	5/64"	3/32"	7/64"	1/8"
NUT	Thickness (H)	.025	.033	.040	.048	.063	.075

MORRIS MANUFACTURING SPECIFICATIONS

THREADS: Complete within two from head unless otherwise specified. Any unthreaded body to be no smaller than minimum pitch diameter or larger than maximum major diameter of thread.

CHAMFER: 45° x 1/2-1 thread on end of threads (may not be measurable depending on how thread is started.)

HEAD BEARING SURFACE: At right angles to body within 2°. On flat and oval, axes of head and body parallel within 2°.

CONCENTRICITY: Heads are concentric within 2% of maximum head diameter or .001" whichever is greater.

FILLET RADIUS: (under head): Not to exceed half the pitch except conical which shall not exceed twice the pitch.

LENGTH: + .005" unless otherwise specified.

SLOT CONCAVITY: Not to exceed 3% of mean head diameter. Slot location within .0015" (.001" on 0000-160).

SLOT DEPTH: The perpendicular distance from bottom of a slot at head circumference to top of head on all numbered series and on UNM flat heads. The standard for all other UNM heads is the distance from the bottom of the slot to the bearing surface of the head.