rpm/feed calculation

[Elad]

Hi,

I'm trying to understand the calculation that gives me the spindle speed and the feed rate from the material.

I'm using the formulas in the help of the material definistion.

I had no problem finding the CS (cutting speed) value.

After i calculate the CS, i need to find the spindle speed, but it doesn't work according to the formula.

spindle speed=(3.82 x CS)/tool diameter

if i calculate according to the formula,i get a different spindle speed then mastercam calculate.

What is the 3.82??i think it has somthing to do with english units.

I need to understand it.it will help me define materials and tools parameters.

and one more little thing to MrDevelopmentGuy :

There are some pepole in the world,that don't use english units,and somtimes it's hard to use the help when it's all in inces.

Thanks.

I hope you could understand my question,

somtimes it's harder to write in english then to speak.

 

[lou]

I dont know if this will help

Metric Formula

Vc . 1000

n = ------------- = min -1

3.14159 . Dw

. = multiplier symbol (metric)

 

3.14159 = Circle, Circumfrence :Dia. ratio

Vc = cutting speed

Dw = effective cutter Diameter

Hope you understand this. Kind of hard to explain. let me know if you need more. Hope this helps......

------------------

Lou Wilson

Cnc Programmer

OMEGA PLASTICS

[email protected]

[This message has been edited by lou (edited 07-17-2001).]

[Simtech]

Basic calculation goea as follows:

RPM = (4 x CS) / D

where,

CS = cutting speed (ft/min)

D = cutter diameter

RPM = spindle revolutions per minute

more specifically,

RPM = (12 x CS) / (pi x D), or

RPM = CS/(pi x (D/12)), where pi = 3.14159...

D is divide by 12 to obtain units in feet because CS is in ft/min

In metric,

RPM = (1000 x CS) / (pi x D), or

RPM = CS / (pi x (D/1000))

where,

D = diameter in mm

CS = cutting speed in m/min

D is divided by 1000 to get diameter in meters.

Luc

 

[ferdelance]

3.82 IS 12 DIVIDED BY PI

[This message has been edited by ferdelance (edited 07-17-2001).]

[Elad]

Thanks guys,