A Throwaway carbide insert was used to machine a steel work pieces with a cutting speed of $$60$$ $$m/min,$$ tool life of $$40$$ minutes was observed, when the cutting speed was increased to $$100$$ $$m/min,$$ the tool life decreased to $$10$$ minutes. The cutting speed for maximum productivity, if tool change time is $$2$$ minutes is

Helix angle of fast helix drill is normally

In a point to point control $$NC$$ machine, the slides are positioned by an integrally mounted stepper motor drive. If the specification of the motor is $$1$$ deg/pulse, and the pitch of the lead screw is $$3.6$$ $$mm,$$ what is the expected positioning accuracy?

A mass of 35 kg is suspended from a weightless bar AC, which is supported by a cable CB and a pin at A as shown in Fig. below. The pin reactions at A on the bar AB are