Thread data sheet

Basic Thread Dimensions

Property mm Inch
Nominal Diameter 39 1.5354
Pitch (Distance) 4 0.1575
Pitch Diameter 36.402 1.4331
Minor Diameter 34.67 1.365
Thread Height 2.165 0.0852
Addendum 1.299 0.0511
Crest (External)
Root (Internal)		 0.5 0.0197
Tap Drill Size
(75% depth)		 35.1 1.382
Lead Angle
(Single Start)		 2°
Thread Family Metric Coarse Pitch (MC)
Relevant Standards ISO 68-1, ISO 9651-1, ISO 965-2, ISO 261,DIN 13
Equivalent InchThread1 9/16 - 6 6-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

Unified Inch Thread Classes

Tolerance Classes

Thread Milling Gcode

Turning Gcode

Over Wire

M39Possible 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

M39 4g (External)

* Permisable values for thread Class 4g

# Description Value (mm) Value (Inch)
es Allowance 0.06 (Ref) 0.0024 (Ref)
d Major Diameter 38.64 - 38.94 1.5213 - 1.5331
d2 Pitch Diameter 36.202 - 36.342 1.4253 - 1.4308
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.828 0.0197 - 0.0326
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 4h (External)

* Permisable values for thread Class 4h

# Description Value (mm) Value (Inch)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 38.7 - 39 1.5236 - 1.5354
d2 Pitch Diameter 36.262 - 36.402 1.4276 - 1.4331
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.828 0.0197 - 0.0326
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 6e (External)

* Permisable values for thread Class 6e

# Description Value (mm) Value (Inch)
es Allowance 0.095 (Ref) 0.0037 (Ref)
d Major Diameter 38.43 - 38.905 1.513 - 1.5317
d2 Pitch Diameter 36.083 - 36.307 1.4206 - 1.4294
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.899 0.0197 - 0.0354
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 6g (External)

* Permisable values for thread Class 6g

# Description Value (mm) Value (Inch)
es Allowance 0.06 (Ref) 0.0024 (Ref)
d Major Diameter 38.465 - 38.94 1.5144 - 1.5331
d2 Pitch Diameter 36.118 - 36.342 1.422 - 1.4308
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.899 0.0197 - 0.0354
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 6h (External)

* Permisable values for thread Class 6h

# Description Value (mm) Value (Inch)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 38.525 - 39 1.5167 - 1.5354
d2 Pitch Diameter 36.178 - 36.402 1.4243 - 1.4331
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.899 0.0197 - 0.0354
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 8e (External)

* Permisable values for thread Class 8e

# Description Value (mm) Value (Inch)
es Allowance 0.095 (Ref) 0.0037 (Ref)
d Major Diameter 38.155 - 38.905 1.5022 - 1.5317
d2 Pitch Diameter 35.952 - 36.307 1.4154 - 1.4294
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.995 0.0197 - 0.0392
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 8g (External)

* Permisable values for thread Class 8g

# Description Value (mm) Value (Inch)
es Allowance 0.06 (Ref) 0.0024 (Ref)
d Major Diameter 38.19 - 38.94 1.5035 - 1.5331
d2 Pitch Diameter 35.987 - 36.342 1.4168 - 1.4308
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.995 0.0197 - 0.0392
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 5g4g (External)

* Permisable values for thread Class 5g4g

# Description Value (mm) Value (Inch)
es Allowance 0.06 (Ref) 0.0024 (Ref)
d Major Diameter 38.64 - 38.94 1.5213 - 1.5331
d2 Pitch Diameter 36.162 - 36.342 1.4237 - 1.4308
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.863 0.0197 - 0.034
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 5h4h (External)

* Permisable values for thread Class 5h4h

# Description Value (mm) Value (Inch)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 38.7 - 39 1.5236 - 1.5354
d2 Pitch Diameter 36.222 - 36.402 1.4261 - 1.4331
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.863 0.0197 - 0.034
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 5g6g (External)

* Permisable values for thread Class 5g6g

# Description Value (mm) Value (Inch)
es Allowance 0.06 (Ref) 0.0024 (Ref)
d Major Diameter 38.465 - 38.94 1.5144 - 1.5331
d2 Pitch Diameter 36.162 - 36.342 1.4237 - 1.4308
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.863 0.0197 - 0.034
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 7g6g (External)

* Permisable values for thread Class 7g6g

# Description Value (mm) Value (Inch)
es Allowance 0.06 (Ref) 0.0024 (Ref)
d Major Diameter 38.465 - 38.94 1.5144 - 1.5331
d2 Pitch Diameter 36.062 - 36.342 1.4198 - 1.4308
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.942 0.0197 - 0.0371
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 7h6h (External)

* Permisable values for thread Class 7h6h

# Description Value (mm) Value (Inch)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 38.525 - 39 1.5167 - 1.5354
d2 Pitch Diameter 36.122 - 36.402 1.4221 - 1.4331
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.942 0.0197 - 0.0371
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 7e6e (External)

* Permisable values for thread Class 7e6e

# Description Value (mm) Value (Inch)
es Allowance 0.095 (Ref) 0.0037 (Ref)
d Major Diameter 38.43 - 38.905 1.513 - 1.5317
d2 Pitch Diameter 36.027 - 36.307 1.4184 - 1.4294
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 0.942 0.0197 - 0.0371
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 9e8e (External)

* Permisable values for thread Class 9e8e

# Description Value (mm) Value (Inch)
es Allowance 0.095 (Ref) 0.0037 (Ref)
d Major Diameter 38.155 - 38.905 1.5022 - 1.5317
d2 Pitch Diameter 35.857 - 36.307 1.4117 - 1.4294
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 1.058 0.0197 - 0.0417
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 9g8g (External)

* Permisable values for thread Class 9g8g

# Description Value (mm) Value (Inch)
es Allowance 0.06 (Ref) 0.0024 (Ref)
d Major Diameter 38.19 - 38.94 1.5035 - 1.5331
d2 Pitch Diameter 35.892 - 36.342 1.4131 - 1.4308
R Root Radius 0.5 (Min) 0.0197 (Min)
C Root Truncation 0.5 - 1.058 0.0197 - 0.0417
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 4H (Internal)

* Permisable values for thread Class 4H

# Description Value (mm) VValue (Inch)
EL Allowance 0 (Ref) 0 (Ref)
D1 Minor Diameter 34.67 - 35.045 1.365 - 1.3797
D2 Pitch Diameter 36.402 - 36.592 1.4331 - 1.4406
D Major Diameter 39 (Min) 1.5354 (Min)
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 5H (Internal)

* Permisable values for thread Class 5H

# Description Value (mm) VValue (Inch)
EL Allowance 0 (Ref) 0 (Ref)
D1 Minor Diameter 34.67 - 35.145 1.365 - 1.3837
D2 Pitch Diameter 36.402 - 36.638 1.4331 - 1.4424
D Major Diameter 39 (Min) 1.5354 (Min)
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 5G (Internal)

* Permisable values for thread Class 5G

# Description Value (mm) VValue (Inch)
EL Allowance 0.06 (Ref) 0.0024 (Ref)
D1 Minor Diameter 34.73 - 35.205 1.3673 - 1.386
D2 Pitch Diameter 36.462 - 36.698 1.4355 - 1.4448
D Major Diameter 39 (Min) 1.5354 (Min)
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 6H (Internal)

* Permisable values for thread Class 6H

# Description Value (mm) VValue (Inch)
EL Allowance 0 (Ref) 0 (Ref)
D1 Minor Diameter 34.67 - 35.27 1.365 - 1.3886
D2 Pitch Diameter 36.402 - 36.702 1.4331 - 1.445
D Major Diameter 39 (Min) 1.5354 (Min)
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 6G (Internal)

* Permisable values for thread Class 6G

# Description Value (mm) VValue (Inch)
EL Allowance 0.06 (Ref) 0.0024 (Ref)
D1 Minor Diameter 34.73 - 35.33 1.3673 - 1.3909
D2 Pitch Diameter 36.462 - 36.762 1.4355 - 1.4473
D Major Diameter 39 (Min) 1.5354 (Min)
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 7H (Internal)

* Permisable values for thread Class 7H

# Description Value (mm) VValue (Inch)
EL Allowance 0 (Ref) 0 (Ref)
D1 Minor Diameter 34.67 - 35.42 1.365 - 1.3945
D2 Pitch Diameter 36.402 - 36.777 1.4331 - 1.4479
D Major Diameter 39 (Min) 1.5354 (Min)
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 7G (Internal)

* Permisable values for thread Class 7G

# Description Value (mm) VValue (Inch)
EL Allowance 0.06 (Ref) 0.0024 (Ref)
D1 Minor Diameter 34.73 - 35.48 1.3673 - 1.3969
D2 Pitch Diameter 36.462 - 36.837 1.4355 - 1.4503
D Major Diameter 39 (Min) 1.5354 (Min)
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

M39 8G (Internal)

* Permisable values for thread Class 8G

# Description Value (mm) VValue (Inch)
EL Allowance 0.06 (Ref) 0.0024 (Ref)
D1 Minor Diameter 34.73 - 35.68 1.3673 - 1.4047
D2 Pitch Diameter 36.462 - 36.937 1.4355 - 1.4542
D Major Diameter 39 (Min) 1.5354 (Min)
LE Normal Length of Engagement 18 - 53 0.7087 - 2.0866

* Back to Thread Class Selection

Over Wire Measurements for M39


* 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 2.021 - 4.041 0.0796 - 0.1591
Ideal Wire Diameter 2.309 0.0909
Possible Wires
From Standard Sets		 * 2.309
* 2.598
* 2.887
* 3.175
* 3.464
 * 0.0825
* 0.0962
* 0.105
* 0.1155
* 0.1283
* 0.1443

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 M39

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=39 MM, P=4 MM, L=40 MM)
(APPLICATION - EXTERNAL TURNING, TOWARDS CHUCK, RH TOOL, RH THREAD)
(FEED - 15 PASSES, FLANK, CONSTANT VOLUME)
(FINISH PASS - 0.043 MM)
(WITH CHAMFER -  NO)
G28 U0 W0
T0101 G99 G97 S816 M03
G00 Z10.0
X 47.6 M08
G76 P010060 Q43 R0.043
G76 X34.093 Z-40.0 P2454 Q622 F4.0 R0.00 
G28 U0 W0
M09
M30
%

CNC Gcode Program for Thread Milling of M39

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=39 MM, P=4 MM, L=40 MM)
(APPLICATION - INTERNAL, RH THREAD, CLIMB MILLING)
(CUTTER - D=19.5 [SINGLE TOOTH])
N1 M06 T1
G54
G90 G40 G17 G94 G21
G00 X0 Y0 S1632 M03
G43 H1 Z20.0 M08
(M-CODE "THROUGH COOLANT ON")
(PASS 1 / 1)
G90 G01 Z-40.5 F2000
G91 G01 G41 D1 X4.875 Y-4.875 F245
G03 X4.875 Y4.875 Z0.5 I0 J4.875 F61
G03 Z4.0 I-9.75 J0 F122
G03 Z4.0 I-9.75 J0
G03 Z4.0 I-9.75 J0
G03 Z4.0 I-9.75 J0
G03 Z4.0 I-9.75 J0
G03 Z4.0 I-9.75 J0
G03 Z4.0 I-9.75 J0
G03 Z4.0 I-9.75 J0
G03 Z4.0 I-9.75 J0
G03 Z4.0 I-9.75 J0
G03 X-4.875 Y4.875 Z0.5 I-4.875 J0
G01 G40 X-4.875 Y-4.875 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.)
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