Quote Originally Posted by Kip View Post
That program looks interesting Irving! I wonder if the chip load calculation in Mach3 would correlate with this program? :cheers:
The program doesnt do chip load or other machining calculations. It is a general purpose framework analysis. The estimation of forces on the cutting tip which give rise to the twisting moments that cause the frame to distort is not an easy one.

A 500W motor (approx 0.75HP output) at 32000rpm gives .17Nm torque, so the max cutting force before the motor stalls on a 4mm cutter is .17/.002 = 85N, however it probably wouldnt get close to that in reality.

Another way to look at it is the cutting force = chip size x chip removal energy = h * w * E

where E = power * tool efficiency / volume removal rate

Aluminium requires about 0.6W per mm3 so a 300W output motor will only acheive a removal rate of 180mm3/sec

E = 300 * .75/1.8e-7= 16.7e6 and therefore force for a .5mm deep cut on a 4mm endmill is around 16.7e6 *.0005 *.002 = 16.7N