54) Find the gear required to cut 3 mm pitch in a lathe having a lead screw of 6 TPI gear available from 20 to 120 teeth by 5 teeth with a special gear of 127 teeth?

55) Which is main criteria to increase the tool life?

56) How the thread are formed in thread rolling?

57) How many number of teeth in translating gear used for cutting metric thread on British lathe?

58) Calculate the change gear ratio to cut a thread of 7/16" lead on a lathe with lead screw of 4 TPI?