HEIDENHAIN TNC 360 User Manual - Manual (Page 120)

TNC 360 5-36
5 Programming Tool Movements
Fig. 5.41: Standard contouring behavior with
R0 and without M90
Fig. 5.42: Contouring behavior with R0 and
M90
5.6 M-Functions for Contouring Behavior and Coordinate Data
The following miscellaneous functions enable you to change the TNC's
standard contouring behavior in certain situations, such as:
• Smoothing corners
• Machining small contour steps
• Machining open contour corners
• Entering machine-referenced coordinates
Smoothing corners: M90
Standard behavior – without M90
At angular transitions such as internal corners and contours without radius
compensation (i.e. with R0), the TNC stops the axes briefly.
Advantages:
• Reduced wear on the machine
• High definition of corners
Note:
In program blocks with radius compensation (RR/RL), at external corners
the TNC automatically inserts a transition arc.
Smoothing corners with M90
The tool moves around corners at constant speed.
Advantages:
• Provides a smoother, more continuous surface
• Reduces machining time
Example application:
Surfaces consisting of several straight line elements.
Duration of effect
The miscellaneous function M90 is effective only in the blocks in which it
is programmed. Operation with servo lag must be active.
A limit value can be set in machine parameter MP7460 (see page 12-9) below which the tool will move at constant
leed rate (valid for operation both with servo lag and with feed precontrol). This value is valid regardiess of M90.
R0
R0