Thread Type Symbol

4/5/2022/ Comments off

The information below can be used to calculate the values of thread tolerances defined by ISO 965/1.

Thread Type Symbols
Internal Thread Symbol

Tolerances are written as a combination of a tolerance band, signified by an alphabetic letter (E, G, e, f, g or h, with uppercase letters signifying internal threads, and lowercase signifying external), and a tolerance class, signified by a number. Grade 6 signifies general use, with smaller numbers being used for stricter tolerance, and higher numbers being used for more loose tolerances.

Thread Type Symbols

It can also be called the thread pitch. Metal screws tend to have more threads per inch than wood screws, for instance. Coarse screws also have a larger pitch measurement than fine screws. A #4-40 UNC-3A x.5 screw has 40 threads per inch. A ¼-20 screw, by comparison, only has 20 threads. Metric thread specifications always begin with thread series designation (for example M or MJ), followed by the fastener’s nominal diameter and thread pitch (both in units of millimeters) separated by the symbol 'x'. Metric thread specification examples MJ6 x 1 - 4H5H M8 x 1.25 - 4h6h LH.

For instance, a 5G tolerance would signify a tolerance that is in the 5th tolerance class of band G.

Thread starter tsturbo; Start date Oct 14, 2004; T. Tsturbo New Member. Oct 14, 2004 #1 Does anybody have a good qaulity pic of the symbol? I am trying to find one.
MIP is an acronym for male iron pipe, and FIP is an acronym for female iron pipe. Outside North America, some US pipe threads are found, as well as many British Standard Pipe threads and ISO 7-1, 7-2, 228-1, and 228-2 threads.
Stress test app with thread pool executor. IntelliJ inspection gives “Cannot resolve symbol” but still compiles code.

Screw threads are usually signified by two tolerances, one for the maximum outside diameter measure from the major diameter of the thread, and one for the pitch diameter, measured from the midpoint of each tooth. For more information on measuring pitch diameter, see our article on how to measure a screw.

As an example, a common screw thread tolerance is 5g6g, which has a 5g tolerance on its pitch diameter, and a 6g tolerance on its external diameter.

Screws threads with identical external tolerances and pitch tolerances are expressed with a single tolerance letter and number. For instance, a screw with a 6g major diameter tolerance and a 6g pitch diameter tolerance would simply be written as “6g”.

The reason that the values for tolerance bands (signified by letters, found in table 1) are written as positive and negative numbers, and the values for tolerance classes (written as numbers, found in tables 2 - 5) are not, is because tolerance classes are applied interchangeably to both internal and external threads, and must be either subtracted or added to a tolerance, dependent on whether the thread is internal or external.

Important Formulae
D	Major Diameter
D1	Minor Diameter Internal Thread
D2	Pitch Diameter Internal Thread
d	Major Diameter External Thread
d1	Minor Diameter External Thread
d2	Pitch Diameter External Thread
T	Tolerance
T_D1	Tolerance for D1
T_D2	Tolerance for D2
T_d1	Tolerance for d1
T_d2	Tolerance for d2
EI	Lower Deviation Internal Thread
ES	Upper Deviation Internal Thread
ei	Lower Deviation External Thread
es	Upper Deviation Internal Thread

Important Calculations
Internal Threads
Min major dia.	basic major dia. + EI (Table 1)
Max minor dia.	min minor dia. + T_D1 (Table 2)
Max pitch dia.	min pitch dia. + T_D2 (Table 4)
External Threads
Max major dia.	basic major dia. − es (Table 1)
Min major dia.	max major dia. − T_d (Table 3)
Min pitch dia.	max pitch dia. − T_d2 (Table 5)

Table 1: Fundamental Deviation Codes For Internal and External Metric Threads (EI/es)
Pitch	Allowance (Fundamental Deviation)
	External Thread				Internal Thread
	e	f	g	h	H	G
	es	es	es	es	EI	EI
0.2	N/A	N/A	-0.017	0	0	+0.017
0.25	N/A	N/A	-0.018	0	0	+0.018
0.3	N/A	N/A	-0.018	0	0	+0.018
0.35	N/A	-0.034	-0.019	0	0	+0.019
0.4	N/A	-0.034	-0.019	0	0	+0.019
0.45	N/A	-0.035	-0.020	0	0	+0.020
0.5	-0.050	-0.036	-0.020	0	0	+0.020
0.6	-0.053	-0.036	-0.021	0	0	+0.021
0.7	-0.056	-0.038	-0.022	0	0	+0.022
0.75	-0.056	-0.038	-0.022	0	0	+0.022
0.8	-0.060	-0.038	-0.024	0	0	+0.024
1	-0.060	-0.040	-0.026	0	0	+0.026
1.25	-0.063	-0.042	-0.028	0	0	+0.028
1.5	-0.067	-0.045	-0.032	0	0	+0.032
1.75	-0.071	-0.048	-0.034	0	0	+0.034
2	-0.071	-0.052	-0.038	0	0	+0.038
2.5	-0.080	-0.058	-0.042	0	0	+0.042
3	-0.085	-0.063	-0.048	0	0	+0.048
3.5	-0.090	-0.070	-0.053	0	0	+0.053
4	-0.095	-0.075	-0.060	0	0	+0.060
4.5	-0.100	-0.080	-0.063	0	0	+0.063
5	-0.106	-0.085	-0.071	0	0	+0.071
5.5	-0.112	-0.090	-0.075	0	0	+0.075
6	-0.118	-0.095	-0.080	0	0	+0.080

Table 2: Minor Diameter Tolerance of Internal Metric Threads (T_D1)
Pitch	4	5	6	7	8
0.2	0.038	N/A	N/A	N/A	N/A
0.25	0.045	0.056	N/A	N/A	N/A
0.3	0.053	0.067	0.085	N/A	N/A
0.35	0.063	0.080	0.100	N/A	N/A
0.4	0.071	0.090	0.112	N/A	N/A
0.45	0.080	0.100	0.125	N/A	N/A
0.5	0.090	0.112	0.140	0.180	N/A
0.6	0.100	0.125	0.160	0.200	N/A
0.7	0.112	0.140	0.180	0.224	N/A
0.75	0.118	0.150	0.190	0.236	N/A
0.8	0.125	0.160	0.200	0.250	0.315
1	0.150	0.190	0.236	0.300	0.375
1.25	0.170	0.212	0.265	0.335	0.425
1.5	0.190	0.236	0.300	0.375	0.475
1.75	0.212	0.265	0.335	0.425	0.530
2	0.236	0.300	0.375	0.475	0.600
2.5	0.280	0.355	0.450	0.560	0.710
3	0.315	0.400	0.500	0.630	0.800
3.5	0.355	0.450	0.560	0.710	0.900
4	0.375	0.475	0.600	0.750	0.950
4.5	0.425	0.530	0.670	0.850	1.060
5	0.450	0.560	0.710	0.900	1.120
5.5	0.475	0.600	0.750	0.950	1.180
6	0.500	0.630	0.800	1.000	1.250

Table 3: Major Diameter Tolerance of External Metric Threads (T_d)
Pitch	Tolerance Grade
Pitch	4	6	8
0.2	0.036	0.056	N/A
0.25	0.042	0.067	N/A
0.3	0.048	0.075	N/A
0.35	0.053	0.085	N/A
0.4	0.060	0.095	N/A
0.45	0.063	0.100	N/A
0.5	0.067	0.106	N/A
0.6	0.080	0.125	N/A
0.7	0.090	0.140	N/A
0.75	0.090	0.140	N/A
0.8	0.095	0.150	0.236
1	0.112	0.180	0.280
1.25	0.132	0.212	0.335
1.5	0.150	0.236	0.375
1.75	0.170	0.265	0.425
2	0.180	0.280	0.450
2.5	0.212	0.335	0.530
3	0.236	0.375	0.600
3.5	0.265	0.425	0.670
4	0.300	0.475	0.750
4.5	0.315	0.500	0.800
5	0.335	0.530	0.850
5.5	0.355	0.560	0.900
6	0.375	0.600	0.950

Table 4: Pitch Diameter Tolerance for Internal Metric Threads (T_D2)
Basic Major Diameter		Pitch	Tolerance Grade
Over	Up to and Including	Pitch	4	5	6	7	8
1.5	2.8	0.2	0.042	N/A	N/A	N/A	N/A
		0.25	0.048	0.060	N/A	N/A	N/A
		0.35	0.053	0.067	0.085	N/A	N/A
		0.4	0.056	0.071	0.090	N/A	N/A
		0.45	0.060	0.075	0.095	N/A	N/A
2.8	5.6	0.35	0.056	0.071	0.090	N/A	N/A
		0.5	0.063	0.080	0.100	0.125	N/A
		0.6	0.071	0.090	0.112	0.140	N/A
		0.7	0.075	0.095	0.118	0.150	N/A
		0.75	0.075	0.095	0.118	0.150	N/A
		0.8	0.080	0.100	0.125	0.160	0.200
5.6	11.2	0.75	0.085	0.106	0.132	0.170	N/A
		1	0.095	0.118	0.150	0.190	0.236
		1.25	0.100	0.125	0.160	0.200	0.250
		1.5	0.112	0.140	0.180	0.224	0.280
11.2	22.4	1	0.100	0.125	0.160	0.200	0.250
		1.25	0.112	0.140	0.180	0.224	0.280
		1.5	0.118	0.150	0.190	0.236	0.300
		1.75	0.125	0.160	0.200	0.250	0.315
		2	0.132	0.170	0.212	0.265	0.335
		2.5	0.140	0.180	0.224	0.280	0.355
22.4	45	1	0.106	0.132	0.170	0.212	N/A
		1.5	0.125	0.160	0.200	0.250	0.315
		2	0.140	0.180	0.224	0.280	0.355
		3	0.170	0.212	0.265	0.335	0.425
		3.5	0.180	0.224	0.280	0.355	0.450
		4	0.190	0.236	0.300	0.375	0.475
		4.5	0.200	0.250	0.315	0.400	0.500
45	90	1.5	0.132	0.170	0.212	0.265	0.335
		2	0.150	0.190	0.236	0.300	0.375
		3	0.180	0.224	0.280	0.355	0.450
		4	0.200	0.250	0.315	0.400	0.500
		5	0.212	0.265	0.335	0.425	0.530
		5.5	0.224	0.280	0.355	0.450	0.560
		6	0.236	0.300	0.375	0.475	0.600
90	180	2	0.160	0.200	0.250	0.315	0.400
		3	0.190	0.236	0.300	0.375	0.475
		4	0.212	0.265	0.335	0.425	0.530
		6	0.250	0.315	0.400	0.500	0.630
180	355	3	0.212	0.265	0.335	0.425	0.530
		4	0.236	0.300	0.375	0.475	0.600
		6	0.265	0.335	0.425	0.530	0.670

Internal Thread Symbol

Table 5: Pitch Diameter Tolerance for External Metric Threads (T_d2)
Basic Major Diameter		Pitch	Tolerance Grade
Over	Up to and Including	Pitch	3	4	5	6	7	8	9
1.5	2.8	0.2	0.025	0.032	0.040	0.050	N/A	N/A	N/A
		0.25	0.028	0.036	0.045	0.056	N/A	N/A	N/A
		0.35	0.032	0.040	0.050	0.063	0.080	N/A	N/A
		0.4	0.034	0.042	0.053	0.067	0.085	N/A	N/A
		0.45	0.036	0.045	0.056	0.071	0.090	N/A	N/A
2.8	5.6	0.35	0.034	0.042	0.053	0.067	0.085	N/A	N/A
		0.5	0.038	0.048	0.060	0.075	0.095	N/A	N/A
		0.6	0.042	0.053	0.067	0.085	0.106	N/A	N/A
		0.7	0.045	0.056	0.071	0.090	0.112	N/A	N/A
		0.75	0.045	0.056	0.071	0.090	0.112	N/A	N/A
		0.8	0.048	0.060	0.075	0.095	0.118	0.150	0.190
5.6	11.2	0.75	0.050	0.063	0.080	0.100	0.125	N/A	N/A
		1	0.056	0.071	0.090	0.112	0.140	0.180	0.224
		1.25	0.060	0.075	0.095	0.118	0.150	0.190	0.236
		1.5	0.067	0.085	0.106	0.132	0.170	0.212	0.265
11.2	22.4	1	0.060	0.075	0.095	0.118	0.150	0.190	0.236
		1.25	0.067	0.085	0.106	0.132	0.170	0.212	0.265
		1.5	0.071	0.090	0.112	0.140	0.180	0.224	0.280
		1.75	0.075	0.095	0.118	0.150	0.190	0.236	0.300
		2	0.080	0.100	0.125	0.160	0.200	0.250	0.315
		2.5	0.085	0.106	0.132	0.170	0.212	0.265	0.335
22.4	45	1	0.063	0.080	0.100	0.125	0.160	0.200	0.250
		1.5	0.075	0.095	0.118	0.150	0.190	0.236	0.300
		2	0.085	0.106	0.132	0.170	0.212	0.265	0.335
		3	0.100	0.125	0.160	0.200	0.250	0.315	0.400
		3.5	0.106	0.132	0.170	0.212	0.265	0.335	0.425
		4	0.112	0.140	0.180	0.224	0.280	0.355	0.450
		4.5	0.118	0.150	0.190	0.236	0.300	0.375	0.475
45	90	1.5	0.080	0.100	0.125	0.160	0.200	0.250	0.315
		2	0.090	0.112	0.140	0.180	0.224	0.280	0.355
		3	0.106	0.132	0.170	0.212	0.265	0.335	0.425
		4	0.118	0.150	0.190	0.236	0.300	0.375	0.475
		5	0.125	0.160	0.200	0.250	0.315	0.400	0.500
		5.5	0.132	0.170	0.212	0.265	0.335	0.425	0.530
		6	0.140	0.180	0.224	0.280	0.355	0.450	0.560
90	180	2	0.095	0.118	0.150	0.190	0.236	0.300	0.375
		3	0.112	0.140	0.180	0.224	0.280	0.355	0.450
		4	0.125	0.160	0.200	0.250	0.315	0.400	0.500
		6	0.150	0.190	0.236	0.300	0.375	0.475	0.600
180	355	3	0.125	0.160	0.200	0.250	0.315	0.400	0.500
		4	0.140	0.180	0.224	0.280	0.355	0.450	0.560
		6	0.160	0.200	0.250	0.315	0.400	0.500	0.630

Quite a while back, one could open the keyboard viewer from the menu bar, choose a font, and see what characters were in it.

There must be something similar now, but the emoji, symbols, & keyboard viewers are rather simplistic. In Pages, there's no other way that I know of to find a character that isn't in any of those, such as the symbol for the Command key.

If I open one of the Adobe apps, I can use the Glyphs to get it, but there has to be some way to do it in Apple apps.

Help!

Thanks.

Mac Pro, OS X El Capitan (10.11.6)

Posted on Aug 30, 2017 12:54 PM