Click the code letter or their description links in the example charts below for definitions of values:

Turning

C N M G 4 3 2
Shape Clearance Angle Tolerance Groove / Hole Size (IC) Thickness Radius

Milling

S E K N 4 2   A F T N
Shape Clearance Angle Tolerance Groove / Hole Size (IC) Thickness Radius Wiper Lead Angle Wiper Clearance Angle Cutting Edge Preparation Cutting Direction

 

 


Shape    
(e.g. "CNMG432" / "CCMT32.51")
          

Code Letter Description Diagram Nose Angle
A

85� parallelogram

  85�
B

82� parallelogram

  82�
C

80� diamond

80�
D

55� diamond

55�
E

75� diamond

75�
H

hexagon

  120�
K

55� parallelogram

55�
L

rectangle

  90�
M

86� diamond

86�
N

55� parallelogram

55�
O

octagon

135�
P

pentagon

108�
R

round

full radius
S

square

90�
T

triangle

60�
V

35� diamond

35�
W

trigon

80�
X

sp. parallelogram

85�

 

 


Clearance or Relief Angle   
(e.g. "CNMG432" / "CCMT32.51")
      

Code Letter Angle Diagram
N
A
B
C
P 11°
D 15°
E 20°
F 25°
G 30°

 

 


Tolerance     
(e.g. "CNMG432" / "CCMT32.51")
         

Code Letter Cornerpoint
(inches)
Thickness
(inches)
Inscribed
Circle (in)
Cornerpoint
(mm)
Thickness
(mm)
Inscribed
Circle (mm)
A .0002" .001" .001" .005mm .025mm .025mm
C .0005" .001" .001" .013mm .025mm .025mm
E .001" .001" .001" .025mm .025mm .025mm
F .0002" .001" .0005" .005mm .025mm .013mm
G .001" .005" .001" .025mm .13mm .025mm
H .0005" .001" .0005" .013mm .025mm .013mm
J .002" .001" .002-.005" .005mm .025mm .05-.13mm
K .0005" .001" .002-.005" .013mm .025mm .05-.13mm
L .001" .001" .002-.005" .025mm .025mm .05-.13mm
M .002-.005" .005" .002-.005" .05-.13mm .13mm .05-.15mm
U .005-.012" .005" .005-.010" .06-.25mm .13mm .08-.25mm

 

 


Hole / Chipbreaker
      (e.g. "CNMG432" / "CCMT32.51")
          

Code Letter Diagram Hole Hole Shape Chipbreaker Type
Null
No   None
A
 
Yes Cylindrical None
B Yes 70-90° double countersink None
D   Yes Cylindrical None
E   No   None
F No   Double-sided
G Yes Cylindrical Double-sided
H
Yes 70-90° single countersink Single-sided
M
Yes Cylindrical, or dbl countersink Single-sided
N
No   None
P
Yes Cylindrical Hi-double positive
Q   Yes 40-60° double countersink None
R No   Single-sided
S
Yes Cylindrical Hi-double positive
T
Yes 40-60° double countersink Single-sided
U   Yes 40-60° double countersink Double-sided
W
Yes 40-60° double countersink None
Z Yes Cylindrical Double-sided hi-double positive

 

 


Size    
(e.g. "CNMG432" / "CCMT32.51")
          

ANSI Code No. Inscribed Circle Size ISO Code No. (metric cutting edge length) by shape code letter of insert
decimal in. fractional in. C D R S T V W
0.5 .0625" 1/16              
1.2 (5) .15625" 5/32 S4 04 (4mm) 03 (3mm) 03 (3mm) 06 (6mm)    
1.5 (6) .1875" 3/16 04 (4mm) 05 (5mm) 04 (4mm) 04 (4mm) 08 (8mm) 08 (8mm) S3
1.8 (7) .21875" 7/32 05 (5mm) 06 (6mm)  05 (5mm)  05 (5mm) 09 (9mm) 09 (9mm) 03 (3mm)
2 .25" 1/4 06 (6mm) 07 (7mm) 06 (6mm) 06 (6mm) 11 (11mm) 11 (11mm) 04 (4mm)
2.5 .3125" 5/16 08 (8mm) 9mm 07 (7mm) 07 (7mm) 13 (13mm) 13 (13mm) 05 (5mm)
3 .375" 3/8 09 (9mm) 11 (11mm) 09 (9mm) 09 (9mm) 16 (16mm) 16 (16mm) 06 (6mm)
3.5 .4375" 7/16 11mm 13mm 11 (11mm) 11 (11mm) 19 (19mm) 19mm 7mm
4 .5" 1/2 12 (12mm) 15 (15mm) 12 (12mm) 12 (12mm) 22 (22mm) 22 (22mm) 08 (8mm)
4.5 .5625" 9/16 14mm 17mm 14 (14mm) 14 (14mm) 24mm 24mm 9mm
5 .625" 5/8 16 (16mm) 19 (9mm) 15 (15mm) 15 (15mm) 27 (27mm) 27 (27mm) 10 (10mm)
5.5 .6875" 11/16 17mm 21mm 17 (17mm) 17 (17mm) 30mm 30mm 11mm
6 .75" 3/4 19 (19mm) 23 (23mm) 19 (19mm) 19 (19mm) 33 (33mm) 33 (33mm) 13 (13mm)
6.5 .8125" 13/16              
7 .875" 7/8 22 (22mm) 27 (27mm) 22 (22mm) 22 (22mm) 38 (38mm) 38 (38mm) 15 (15mm)
8 1" 1 25 (25mm) 31 (31mm) 25 (25mm) 25 (25mm) 44 (44mm) 44 (44mm) 17 (17mm)
10 1.25" 1-1/4 32 (32mm) 38mm 31 (31mm) 31 (31mm) 54 (54mm) 54 (54mm) 21 (21mm)
  1.26"       32 (32mm)        

 

 


Thickness    
(e.g. "CNMG432" / "CCMT32.51")
         

ANSI
Code No.
ISO
Code No.
Decimal
Value
Fractional
Value
Millimeter
Value
.5 (1) - 0.03125" 1/32 0.79mm
.6 T0 0.040"   1.00mm
1 (2) 01 0.0625" 1/16 1.59mm
1.2 T1 0.078" 5/64 1.98mm
1.5 (3) 02 0.094" 3/32 2.38mm
  T2 0.109" 7/64 2.78mm
2 03 0.125" 1/8 3.18mm
2.5 T3 0.156" 5/32 3.97mm
3 04 0.187" 3/16 4.76mm
  05 0.219" 7/32 5.56mm
4 06 0.25" 1/4 6.35mm
5 07 0.313" 5/16 7.9mm
6 09 0.375" 3/8 9.53mm
8   0.5" 1/2 12.7mm

 

 


Radius
    (e.g. "CNMG432" / "CCMT32.51")
          

ANSI
Code No.
ISO
Code No.
Decimal
Value
Fractional
Value
Millimeter
Value
Null Null Wiper flat Wiper flat Wiper flat
V M0 0 0 0
0.2 00 0.004"   0.1mm
X   0.004"   0.1mm
0  00 0.004"   0.2mm
0.5   0.008"   0.2mm
Y   0.008"   0.2mm
1 04 0.016" 1/64 0.4mm
  05 0.020"   0.5mm
2 08 0.031" 1/32 0.8mm
  10 0.040"   1.02mm
3 12 0.047" 3/64 1.2mm
4 16 0.062" 1/16 1.6mm
5 20 0.078" 5/64 2mm
6 24 0.094" 3/32 2.4mm
7 29 0.109" 7/64 2.9mm
8 32 0.125" 1/8 3.2mm

 

 


Wiper Lead Angle 
     (e.g. "SEKN42AFTN")
           

Code Letter Angle
A 45°
D 60°
K 60°
E 75°
L 75°
P
S 75°

 

 


Wiper Clearance Angle
     (e.g. "SEKN42AFTN")
   

Code Letter Angle
C
D 15°
E 20°
F 25-26°
G 30°
N
P 11°

 

 


Cutting Edge Preparation
    (e.g. "SEKN42AFTN")
   

Code Letter Edge Preparation
F sharp
E honed
T T-land
S honed T-land
X special chamfer

 

 


Cutting Direction   
   (e.g. "SEKN42AFTN")
   

Code Letter Direction
R right-hand cutting only
L left-hand cutting only
N both right-hand and left-hand cutting