5 cutting data calculator, Application, Cutting data calculator – HEIDENHAIN TNC 640 (34059x-05) ISO programming User Manual
Page 147: Cutting data calculator 4.5
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Cutting data calculator
4.5
4
TNC 640 | User's ManualDIN/ISO Programming | 1/2015
147
4.5
Cutting data calculator
Application
With the cutting data calculator you can calculate the spindle speed
and the feed rate for a machine process. Then you can load the
calculated values into an opened feed-rate or spindle-speed dialog
box in the NC program.
You cannot perform any cutting data calculation
in turning mode with the cutting data calculator
because the feed rate and spindle speed data are
different in turning mode from milling mode. During
turning, feed rates are usually defined in mm per
revolution (mm/rev) (
M136), but the cutting data
calculator always calculates in mm per minute
(mm/min). In addition, the radius in the cutting data
calculator is with respect to the tool, but turning
operations need the tool diameter.
To open the cutting data calculator, press the
CUTTING DATA
CALCULATOR soft key. The TNC shows the soft key if you
open the calculator (
CALC key)
open the dialog field for spindle speed input in the T block
open the dialog field for feed rate input in positioning blocks or
cycles
enter a feed rate in manual operation (F soft key)
enter a spindle speed in manual operation (S soft key)
The cutting data calculator is displayed with different input fields
depending on whether you calculate a spindle speed or a feed rate:
Window or spindle speed calculation:
Code letter
Meaning
R:
Tool radius (mm)
VC:
Cutting speed (m/min)
S=
Result for spindle speed (rev/min)