8 Basic CNC Programming
8.4 NC Codes
114
Note that an NC program will use the offset values as listed in this window, without converting for
metric or imperial systems. The Units selection area in the window converts the values in this window.
8.4.6.10.
Scaling Group
Use the Scaling codes to scale one or more axes of a part from a fixed scaling origin. You can scale the
entire piece uniformly, or set different scaling factors for each axis.
Use a P Code to scale an entire piece uniformly along each axis. When you specify a value for P,
subsequent motions are scaled by that value, starting from the scaling center. The control software
measures the distance from the scaling center to the start and end points of the shape, then multiplies
those values by the P value.
The code I is used to specify the X axis center of scaling, see
8.4.8. I Code: X Axis Coordinate of Center
Point, pg. 116. The J code is used to specify the Y axis center of scaling, see
Coordinate of Center Point, pg. 117. The code K is used to specify the Z axis center of scaling, see
K Code: Z Axis Coordinate of Center Point, pg. 117.
If you do not specify any of the coordinates for the scaling center, the current position for unspecified
axes becomes the scaling center coordinate
Product Care
Using a P Code to scale an entire piece will affect the Z axis, which will affect your
programmed depths of cuts. Use caution when performing scaling operations.
Use the following codes for scaling:
Info Table: Scaling Group
Code
Function
G50
Cancels scaling
G51
Invokes scaling
P
Uniform scale multiplier
The example below demonstrates the use of scaling:
