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28 — M
achinist
c
alc™
/ M
achinist
c
alc™
P
ro
3. Store as the Diameter:
= d
DIA 0.228
INCH
4. Enter the RPM:
7 5 0 R
RPM
750.
5. Calculate the Cutting Speed:
C
*
CUT 14.
M/MIN
6. Return calculator to U.S. Mode:
g S S S +
US UnITS
* Repeated presses of
C
will toggle through the inputs and outputs,
starting with the entered Diameter.
rPm (SPINDlE SPEED)
RPM
is the rotational speed of the spindle in revolutions per
minute. In a milling machine or drill, the Spindle Speed is the
rotation of the attached cutting tool. In a turning machine, it is
the rotation of the attached workpiece. RPM can be calculated
given values for Diameter and Cutting Speed.
RPM -
Milling
Calculate the Spindle Speed (RPM) when milling with a 3/8” bit
at a Cutting Speed of 300 sfm (surface feet per minute):
RPM
Diameter: ⅜
″
(cont'd)
KeYSTROKe
DISPLAY