Thread data sheet

Basic Thread Dimensions

Property Inch mm
Nominal Diameter 0.625 15.875
Pitch (TPI)28
Pitch (Distance) 0.0357 0.907
Pitch Diameter 0.6018 15.286
Minor Diameter 0.5825 14.796
Thread Height 0.0193 0.49
Addendum 0.0116 0.295
Crest (External)
Root (Internal)
0.0045 0.114
Tap Drill Size
(75% depth)
0.59 14.99
Lead Angle
(Single Start)
1.08°
Thread Family Unified Constant Pitch 28 TPI (28-UN)
Relevant Standards ASME B1.1-2003
Equivalent MetricThreadM16 X 1

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

Choose the Threading Data you want to explore


5/8 - 28 28-UNPossible Thread Classes

External Threads

2A, 3A

Metric ISO External Thread - Tolerance sketch

Internal Threads

2B, 3B

Metric ISO Internal Thread - Tolerance sketch

5/8 - 28 28-UN 2A (External)

* Permisable values for thread Class 2A

# Description Value (Inch) Value (mm)
es Allowance 0.0011 (Ref) 0.028 (Ref)
d Major Diameter 0.6174 - 0.6239 15.682 - 15.847
d2 Pitch Diameter 0.5972 - 0.6007 15.169 - 15.258
d3 Minor Diameter
(UNR Only)
0.5814 (Ref) 14.768 (Ref)
α Varation of 30° anngle (+/-) 1.3333°
P Varation of pitch (+/-) 0.001 (Ref) 0.025 (Ref)

* Values are calculated for Length of engagement of 5xPitch. For calculations of different engagement length use the Thread Calculator'

* Back to Thread Class Selection


5/8 - 28 28-UN 3A (External)

* Permisable values for thread Class 3A

# Description Value (Inch) Value (mm)
es Allowance 0 (Ref) 0 (Ref)
d Major Diameter 0.6185 - 0.625 15.71 - 15.875
d2 Pitch Diameter 0.5991 - 0.6018 15.217 - 15.286
d3 Minor Diameter
(UNR Only)
0.5825 (Ref) 14.796 (Ref)
α Varation of 30° anngle (+/-) 1.3333°
P Varation of pitch (+/-) 0.0008 (Ref) 0.02 (Ref)

* Values are calculated for Length of engagement of 5xPitch. For calculations of different engagement length use the Thread Calculator'

* Back to Thread Class Selection


5/8 - 28 28-UN 2B (Internal)

* Permisable values for thread Class 2B

# Description Value (Inch) VValue (mm)
D1 Minor Diameter 0.586 - 0.595 14.884 - 15.113
D2 Pitch Diameter 0.6018 - 0.6064 15.286 - 15.403
D Major Diameter 0.6250 (Min) 15.875 (Min)
α Varation of 30° anngle (+/-) 1.3333°
P Varation of Pitch (+/-) 0.0013 (Ref) 0.033 (Ref)

* Values are calculated for Length of engagement of 5xPitch. For calculations of different engagement length use the Thread Calculator

* Back to Thread Class Selection


5/8 - 28 28-UN 3B (Internal)

* Permisable values for thread Class 3B

# Description Value (Inch) VValue (mm)
D1 Minor Diameter 0.5863 - 0.5926 14.892 - 15.052
D2 Pitch Diameter 0.6018 - 0.6053 15.286 - 15.375
D Major Diameter 0.6250 (Min) 15.875 (Min)
α Varation of 30° anngle (+/-) 1.3333°
P Varation of Pitch (+/-) 0.001 (Ref) 0.025 (Ref)

* Values are calculated for Length of engagement of 5xPitch. For calculations of different engagement length use the Thread Calculator

* Back to Thread Class Selection


Tap Drill Sizes for 5/8 - 28 28-UN

  • 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% 0.599 15.23
60% 0.597 15.17
65% 0.595 15.11
70% 0.593 15.05
75% 0.590 14.99
80% 0.588 14.93
85% 0.586 14.87

Over Wire Measurements for 5/8 - 28 28-UN


* 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

Inch mm
Permissible Wire Diameter Range 0.018 - 0.0361 0.458 - 0.916
Ideal Wire Diameter 0.0206 0.524
Possible Wires
From Standard Sets
* 0.018
* 0.0193
* 0.0206
* 0.0214
* 0.0222
* 0.0241
* 0.0262
* 0.0289
* 0.462
* 0.52
* 0.577
* 0.722
* 0.866

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 5/8 - 28 28-UN

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=0.625 INCH, P=0.035714285714286 INCH, L=0.35714285714286 INCH)
(APPLICATION - EXTERNAL TURNING, TOWARDS CHUCK, RH TOOL, RH THREAD)
(FEED - 17 PASSES, FLANK, CONSTANT VOLUME)
(FINISH PASS - 0.0003 INCH)
(WITH CHAMFER -  NO)
G28 U0 W0
T0101 G99 G97 S1833 M03
G00 Z5.1
X 26.0 M08
G76 P010060 Q8 R0.008
G76 X14.762 Z-9.071 P556 Q133 F0.907 R0.00 
G28 U0 W0
M09
M30
%

CNC Gcode Program for Thread Milling of 5/8 - 28 28-UN

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=0.625 INCH, P=0.035714285714286 INCH, L=0.35714285714286 INCH)
(APPLICATION - INTERNAL, RH THREAD, CLIMB MILLING)
(CUTTER - D=0.3125 [SINGLE TOOTH])
N1 M06 T1
G54
G90 G40 G17 G94 G21
G00 X0 Y0 S3667 M03
G43 H1 Z25.4 M08
(M-CODE "THROUGH COOLANT ON")
(PASS 1 / 1)
G90 G01 Z-9.1848 F2032
G91 G01 G41 D1 X1.9844 Y-1.9844 F559
G03 X1.9844 Y1.9844 Z0.1134 I0 J1.9844 F140
G03 Z0.9071 I-3.9688 J0 F279
G03 Z0.9071 I-3.9688 J0
G03 Z0.9071 I-3.9688 J0
G03 Z0.9071 I-3.9688 J0
G03 Z0.9071 I-3.9688 J0
G03 Z0.9071 I-3.9688 J0
G03 Z0.9071 I-3.9688 J0
G03 Z0.9071 I-3.9688 J0
G03 Z0.9071 I-3.9688 J0
G03 Z0.9071 I-3.9688 J0
G03 X-1.9844 Y1.9844 Z0.1134 I-1.9844 J0
G01 G40 X-1.9844 Y-1.9844 F2032
G90 G00 Z25.4
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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