Chapter 6 Machining Center Carbide Insert Fundamentals 129
Figure 6-11. This graphic identifies the meaning of each letter or number in the standard identification
system used to classify carbide inserts. The system was developed by the American National Standards
Institute (ANSI).
Tolerances
Insert IC Thickness
A = ±.001 ±.001
C = ±.001 ±.001
E = ±.001 ±.001
G = ±.001 ±.005
M* = ±.002 ±.005
±.004 ±.005
U* = ±.003 ±.005
±.010 ±.005
*Exact tolerance is determined
by the size of the insert
Shape
C = Diamond 80°
D = Diamond 55°
R = Round
S = Square
T = Triangle
V = Diamond 35°
W = Trigon 80°
Cutting edge condition
F = Sharp cutting edges
E = Honed cutting edges
T = Chamfered cutting edges
S = Chamfered and honed cutting edges
K = Double chamfered cutting edges
P = Double chamfered and rounded cutting edges
Size
For equal sided inserts IC in 1/8ths of an inch
Examples:
1/8″ = 1 5/32″ = 1.2 3/16″ = 1.5
7/32″ = 1.8 1/4″ = 2 5/16″ = 2.5
3/8″ = 3 1/2″ = 4 5/8″ = 5
3/4″ = 6 7/8″ = 7 1″ = 8
1 1/4″ = 10
Rectangle and parallelogram inserts require
two digits:
The first digit is the number of 1/8ths in width.
The second digit is the number of 1/4ths in
length.
Insert clearance
angle
N = 0°
B = 5°
C = 7°
P = 11°
D = 15°
E = 20°
Type
A = With hole, no chipbreaker
B = With hole and one countersink
E = Smaller than 1/4″ IC without hole
G = With hole and chipbreaker on both faces
H = With hole, countersink and chipgroove
M = With hole and chipbreaker on one face only
R = Without hole, chipbreaker on one face only
T = C-Lock hole with chipbreaker on one face only
W = C-Lock hole, no chipbreaker
Nose radius
0.0 = Sharp to 1/512
0 = Sharp to 1/256
0.5 = 1/128
1 = 1/64
2 = 1/32
3 = 3/64
4 = 1/16
6 = 3/32
8 = 1/8
Thickness
Number of 1/32nds on
inserts less than 1/4″ IC
Number of 1/16ths on
inserts 1/4″ IC and over
Manufacturer’s option
e.g. chipbreaker designation
F = Finishing
M = Medium
R = Roughing
1 = For low feed rates
and easy conditions
9 = For high feed rates
and rough conditions
T N G M 5 4 6 M2 –