Thread data sheet

Basic Thread Dimensions

Property mm Inch
Nominal Diameter 12 0.4724
Pitch (Distance) 1.75 0.0689
Pitch Diameter 10.863 0.4277
Minor Diameter 10.106 0.3979
Thread Height 0.947 0.0373
Addendum 0.568 0.0224
Crest (External)
Root (Internal)		 0.219 0.0086
Tap Drill Size
(75% depth)		 10.29 0.405
Lead Angle
(Single Start)		 2.94°
Thread Family Metric Coarse Pitch (MC)
Relevant Standards ISO 68-1, ISO 9651-1, ISO 965-2, ISO 261,DIN 13
Equivalent InchThread1/2 - 16 16-UN

For more threading data scroll down, or use the Thread Calculator

Choose the Threading Data you want to explore

Unified Inch Thread Classes

Tolerance Classes

Thread Milling CNC program

Thread Milling Gcode

Turning Gcode

Over Wire

Tap Drill Size

Unified Inch Thread Classes

Tolerance Classes

Thread Milling Gcode

Turning Gcode

Over Wire

Tap Drill Size

M12Possible Thread Classes

External Threads

4g, 4h, 6e, 6g, 6h, 8e, 8g, 5g4g, 5h4h, 5g6g, 7g6g, 7h6h, 7e6e, 9e8e, 9g8g

Metric ISO External Thread - Tolerance sketch

Internal Threads

4H, 5H, 5G, 6H, 6G, 7H, 7G, 8G

Metric ISO Internal Thread - Tolerance sketch

M12 4g (External)

* Permisable values for thread Class 4g

# Description Value (mm) Value (Inch)
es Allowance 0.034 (Ref) 0.0013 (Ref)
d Major Diameter 11.796 - 11.966 0.4644 - 0.4711
d2 Pitch Diameter 10.734 - 10.829 0.4226 - 0.4263
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.391 0.0086 - 0.0154
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 4h (External)

* Permisable values for thread Class 4h

# Description Value (mm) Value (Inch)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 11.83 - 12 0.4657 - 0.4724
d2 Pitch Diameter 10.768 - 10.863 0.4239 - 0.4277
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.391 0.0086 - 0.0154
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 6e (External)

* Permisable values for thread Class 6e

# Description Value (mm) Value (Inch)
es Allowance 0.071 (Ref) 0.0028 (Ref)
d Major Diameter 11.664 - 11.929 0.4592 - 0.4696
d2 Pitch Diameter 10.642 - 10.792 0.419 - 0.4249
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.432 0.0086 - 0.017
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 6g (External)

* Permisable values for thread Class 6g

# Description Value (mm) Value (Inch)
es Allowance 0.034 (Ref) 0.0013 (Ref)
d Major Diameter 11.701 - 11.966 0.4607 - 0.4711
d2 Pitch Diameter 10.679 - 10.829 0.4204 - 0.4263
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.432 0.0086 - 0.017
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 6h (External)

* Permisable values for thread Class 6h

# Description Value (mm) Value (Inch)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 11.735 - 12 0.462 - 0.4724
d2 Pitch Diameter 10.713 - 10.863 0.4218 - 0.4277
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.432 0.0086 - 0.017
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 8e (External)

* Permisable values for thread Class 8e

# Description Value (mm) Value (Inch)
es Allowance 0.071 (Ref) 0.0028 (Ref)
d Major Diameter 11.504 - 11.929 0.4529 - 0.4696
d2 Pitch Diameter 10.556 - 10.792 0.4156 - 0.4249
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.487 0.0086 - 0.0192
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 8g (External)

* Permisable values for thread Class 8g

# Description Value (mm) Value (Inch)
es Allowance 0.034 (Ref) 0.0013 (Ref)
d Major Diameter 11.541 - 11.966 0.4544 - 0.4711
d2 Pitch Diameter 10.593 - 10.829 0.417 - 0.4263
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.487 0.0086 - 0.0192
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 5g4g (External)

* Permisable values for thread Class 5g4g

# Description Value (mm) Value (Inch)
es Allowance 0.034 (Ref) 0.0013 (Ref)
d Major Diameter 11.796 - 11.966 0.4644 - 0.4711
d2 Pitch Diameter 10.711 - 10.829 0.4217 - 0.4263
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.409 0.0086 - 0.0161
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 5h4h (External)

* Permisable values for thread Class 5h4h

# Description Value (mm) Value (Inch)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 11.83 - 12 0.4657 - 0.4724
d2 Pitch Diameter 10.745 - 10.863 0.423 - 0.4277
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.409 0.0086 - 0.0161
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 5g6g (External)

* Permisable values for thread Class 5g6g

# Description Value (mm) Value (Inch)
es Allowance 0.034 (Ref) 0.0013 (Ref)
d Major Diameter 11.701 - 11.966 0.4607 - 0.4711
d2 Pitch Diameter 10.711 - 10.829 0.4217 - 0.4263
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.409 0.0086 - 0.0161
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 7g6g (External)

* Permisable values for thread Class 7g6g

# Description Value (mm) Value (Inch)
es Allowance 0.034 (Ref) 0.0013 (Ref)
d Major Diameter 11.701 - 11.966 0.4607 - 0.4711
d2 Pitch Diameter 10.639 - 10.829 0.4189 - 0.4263
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.459 0.0086 - 0.0181
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 7h6h (External)

* Permisable values for thread Class 7h6h

# Description Value (mm) Value (Inch)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 11.735 - 12 0.462 - 0.4724
d2 Pitch Diameter 10.673 - 10.863 0.4202 - 0.4277
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.459 0.0086 - 0.0181
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 7e6e (External)

* Permisable values for thread Class 7e6e

# Description Value (mm) Value (Inch)
es Allowance 0.071 (Ref) 0.0028 (Ref)
d Major Diameter 11.664 - 11.929 0.4592 - 0.4696
d2 Pitch Diameter 10.602 - 10.792 0.4174 - 0.4249
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.459 0.0086 - 0.0181
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 9e8e (External)

* Permisable values for thread Class 9e8e

# Description Value (mm) Value (Inch)
es Allowance 0.071 (Ref) 0.0028 (Ref)
d Major Diameter 11.504 - 11.929 0.4529 - 0.4696
d2 Pitch Diameter 10.492 - 10.792 0.4131 - 0.4249
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.525 0.0086 - 0.0207
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 9g8g (External)

* Permisable values for thread Class 9g8g

# Description Value (mm) Value (Inch)
es Allowance 0.034 (Ref) 0.0013 (Ref)
d Major Diameter 11.541 - 11.966 0.4544 - 0.4711
d2 Pitch Diameter 10.529 - 10.829 0.4145 - 0.4263
R Root Radius 0.219 (Min) 0.0086 (Min)
C Root Truncation 0.219 - 0.525 0.0086 - 0.0207
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 4H (Internal)

* Permisable values for thread Class 4H

# Description Value (mm) VValue (Inch)
EL Allowance 0 (Ref) 0 (Ref)
D1 Minor Diameter 10.106 - 10.318 0.3979 - 0.4062
D2 Pitch Diameter 10.863 - 10.988 0.4277 - 0.4326
D Major Diameter 12 (Min) 0.4724 (Min)
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 5H (Internal)

* Permisable values for thread Class 5H

# Description Value (mm) VValue (Inch)
EL Allowance 0 (Ref) 0 (Ref)
D1 Minor Diameter 10.106 - 10.371 0.3979 - 0.4083
D2 Pitch Diameter 10.863 - 11.023 0.4277 - 0.434
D Major Diameter 12 (Min) 0.4724 (Min)
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 5G (Internal)

* Permisable values for thread Class 5G

# Description Value (mm) VValue (Inch)
EL Allowance 0.034 (Ref) 0.0013 (Ref)
D1 Minor Diameter 10.14 - 10.405 0.3992 - 0.4096
D2 Pitch Diameter 10.897 - 11.057 0.429 - 0.4353
D Major Diameter 12 (Min) 0.4724 (Min)
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 6H (Internal)

* Permisable values for thread Class 6H

# Description Value (mm) VValue (Inch)
EL Allowance 0 (Ref) 0 (Ref)
D1 Minor Diameter 10.106 - 10.441 0.3979 - 0.4111
D2 Pitch Diameter 10.863 - 11.063 0.4277 - 0.4356
D Major Diameter 12 (Min) 0.4724 (Min)
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 6G (Internal)

* Permisable values for thread Class 6G

# Description Value (mm) VValue (Inch)
EL Allowance 0.034 (Ref) 0.0013 (Ref)
D1 Minor Diameter 10.14 - 10.475 0.3992 - 0.4124
D2 Pitch Diameter 10.897 - 11.097 0.429 - 0.4369
D Major Diameter 12 (Min) 0.4724 (Min)
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 7H (Internal)

* Permisable values for thread Class 7H

# Description Value (mm) VValue (Inch)
EL Allowance 0 (Ref) 0 (Ref)
D1 Minor Diameter 10.106 - 10.531 0.3979 - 0.4146
D2 Pitch Diameter 10.863 - 11.113 0.4277 - 0.4375
D Major Diameter 12 (Min) 0.4724 (Min)
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 7G (Internal)

* Permisable values for thread Class 7G

# Description Value (mm) VValue (Inch)
EL Allowance 0.034 (Ref) 0.0013 (Ref)
D1 Minor Diameter 10.14 - 10.565 0.3992 - 0.4159
D2 Pitch Diameter 10.897 - 11.147 0.429 - 0.4389
D Major Diameter 12 (Min) 0.4724 (Min)
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

M12 8G (Internal)

* Permisable values for thread Class 8G

# Description Value (mm) VValue (Inch)
EL Allowance 0.034 (Ref) 0.0013 (Ref)
D1 Minor Diameter 10.14 - 10.67 0.3992 - 0.4201
D2 Pitch Diameter 10.897 - 11.212 0.429 - 0.4414
D Major Diameter 12 (Min) 0.4724 (Min)
LE Normal Length of Engagement 6 - 18 0.2362 - 0.7087

* Back to Thread Class Selection

Tap Drill Sizes for M12

  • If not specified, assume a thread depth of 75%.
  • You can learn more about thread depth in tapping here.
  • To get the tap drill size in other depths, use our Tap Drill Size Calculator .
Thread Depth Tap Drill Size (Inch) Tap Drill Size (mm)
55% 0.423 10.75
60% 0.419 10.64
65% 0.414 10.52
70% 0.410 10.41
75% 0.405 10.29
80% 0.401 10.18
85% 0.396 10.07

Over Wire Measurements for M12


* OverWire is a measuring method to obatin the pitch diameter of threads. It is mostly used when a manufacturer does not have a Go/Nogo gauge for a thread. You can learn more about it here

mm Inch
Permissible Wire Diameter Range 0.884 - 1.768 0.0348 - 0.0696
Ideal Wire Diameter 1.01 0.0398
Possible Wires
From Standard Sets		 * 1.01
* 1.155
* 1.443
* 1.732
 * 0.0642

Once you know your wire diameter, you need to find out what is the premissable Measurement for your pitch diameter (Depending on the class). Use our Over Wire Calculator to find out!

CNC Gcode Program for Turning of M12

The below sample Gcode is configured for:

  • Fanuc Controller
  • External RH Thread
  • Right hand tool, machining towards the chuck
  • Flank Infeed method with contant volume
  • Flank Infeed method with contant volume
  • Cutting conditions for steel
  • Default number of passes

You can configure all the above parameters and much more in our Thread Turning Gcode Generator 


%
O0100
(MACHINING DOCTOR - THREADING CNC PROGRAM)
(CONTROLER - FANUC A)
(THREAD - D=12 MM, P=1.75 MM, L=17.5 MM)
(APPLICATION - EXTERNAL TURNING, TOWARDS CHUCK, RH TOOL, RH THREAD)
(FEED - 9 PASSES, FLANK, CONSTANT VOLUME)
(FINISH PASS - 0.031 MM)
(WITH CHAMFER -  NO)
G28 U0 W0
T0101 G99 G97 S2653 M03
G00 Z5.3
X 15.2 M08
G76 P010060 Q31 R0.031
G76 X9.853 Z-17.5 P1074 Q348 F1.75 R0.00 
G28 U0 W0
M09
M30
%

CNC Gcode Program for Thread Milling of M12

The below sample Gcode is configured for:

  • Fanuc Controller
  • Internal RH Thread
  • Climb Milling
  • Cutter diameter: 70% of the thread diameter
  • Single tooth Thread Mill cutter
  • Cutting conditions for steel
  • One radial pass

You can configure all the above parameters and much more in our Thread Milling Gcode Generator 


%
O101
(WWW.MACHININGDOCTOR.COM - THREADMILLING PROGRAM)
(CONTROLER - FANUC)
(THREAD - D=12 MM, P=1.75 MM, L=17.5 MM)
(APPLICATION - INTERNAL, RH THREAD, CLIMB MILLING)
(CUTTER - D=6 [SINGLE TOOTH])
N1 M06 T1
G54
G90 G40 G17 G94 G21
G00 X0 Y0 S5305 M03
G43 H1 Z20.0 M08
(M-CODE "THROUGH COOLANT ON")
(PASS 1 / 1)
G90 G01 Z-17.719 F2000
G91 G01 G41 D1 X1.5 Y-1.5 F796
G03 X1.5 Y1.5 Z0.219 I0 J1.5 F199
G03 Z1.75 I-3.0 J0 F398
G03 Z1.75 I-3.0 J0
G03 Z1.75 I-3.0 J0
G03 Z1.75 I-3.0 J0
G03 Z1.75 I-3.0 J0
G03 Z1.75 I-3.0 J0
G03 Z1.75 I-3.0 J0
G03 Z1.75 I-3.0 J0
G03 Z1.75 I-3.0 J0
G03 Z1.75 I-3.0 J0
G03 X-1.5 Y1.5 Z0.219 I-1.5 J0
G01 G40 X-1.5 Y-1.5 F2000
G90 G00 Z20.0
M30
(PLEASE NOTE THIS GCODE HAS NOT BEEN TESTED ON YOUR MACHINE AND SETUP. WE CANNOT GUARANTEE ITS ACCURACY OR COMPATIBILITY. NOTE THAT YOU ARE USING IT AT YOUR OWN RISK, AND WE SHALL NOT BE HELD LIABLE FOR ANY DAMAGES OR LOSSES ARISING FROM THE USE OF THIS PROGRAM.)
%

Start typing and press enter to search

Scroll to Top