# Relation between rpm ,frequency & g in CNC cutting machine.

Discussion in 'General Electronics Chat' started by lalitha.e, Jul 18, 2013.

1. ### lalitha.e Thread Starter New Member

Aug 23, 2012
1
0
Pl tell the conversion from rpm to frequency & how to calculate or relate to output of accelerometer in g while using vibration indicator to measure velocity BY MOUNTING ACCELEROMETER ON HEAD STOCK COVER OF CNC CUTTING MACHINE.
THANKS.

2. ### WBahn Moderator

Mar 31, 2012
17,716
4,788
rpm of what?

frequency of what?

By "head stock cover", are you talking about a part of the machine that is not moving?

Please describe in more detail what you are trying to do? This almost sounds like you are trying to measure the vibration in a non-moving cover and somehow determine how fast the headstock is rotating?

Surely I'm misunderstanding you.

Now, I would not be surprised to see a correlation between the two -- quite the opposite --so I'm not saying it is not possible. But the rotation of the headstock is probably going to excite a lot of vibrational modes in the cover and picking out the right one to measure may not be easy.

3. ### BillB3857 Senior Member

Feb 28, 2009
2,400
348
IF (big if) you are talking about having an accelerometer mounted to the spindle (part that holds the rotary cutter), the frequency/RPM relationship is 60Hz=3600RPM, 50Hz=3000RPM, etc. Magnitude of the signal will represent the amount of displacement and will depend upon the gain/sensitivity of the amplifier and accelerometer. If you are trying to measure vibration due to the cutting process, the above figures would need to be modified to account for the number of cutting flutes.