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I want to build home made CNC using this parts.

I ask, if I use this motors what can be my cnc's bandwidth?

Yes Electrical time constants, servo controller, Friction and mass of axis plays importand role on BW. Lets forget these parameters.

I will use this motor and other parts (screw, nuts..)

Now i want to know if i use this motors what happens the max axis speed of my cnc? I find an answer for this question but i am not sure, I want learn your ideas.

Motor labels says 3000rpm and screws has 4 mm/rev. (p=4)

We can calculate the maximum velocity of lineer motion.

n=3000/60 = 50 rev.per sec.

vmax = p * n = 4 * 50 = 200 mm/sec.

My machine working area 300x300mm

Now I ask this question: If i want to draw circle with this motors what happens the max speed?

Max radius is 150 mm. (Machine limits)

we know sin and cos functions draw circle.

Function of X axis position

Px = 150 * sin(wt)

Function of Y axis position function

Py = 150 * cos(wt)

we can calculate the velocity functions

Vx=150 * w * cos(wt)

Vxmax = 150 * w = 200 mm/sec

w = 1.33 rad/sec

w = 2pi/T T=2pi/w = 4.7 sec. Appox. 5 sec.

F = 1/T = 1/5 = 0.2Hz

My machine can draw circle (r=150mm) in 5 seconds.

My cnc's position control servo bandwidth must be minimum 02 * 10 = 2 Hz

Am I wrong? I am waiting your responses.

Thanks.