A - 0° Lead
B - 15° Lead
C - Square Nose
D - 40° Lead
E - 30° Lead
F - Offset Facing
G - Offset Turning |
Shouldering
Turning to Lead Angle
Grooving & Facing
Undercutting and Chamfer Threading
Facing
Shouldering |
R - Right
L - Left |
Under 40 size shank is square
Expressed in 1/16"
No. 16 = 16/16 or 1" square
Over #40 size shank is rectangular
1st digit width in 1/8" increments
2nd digit height in 1/4" increments |