13 February 2017

Difference between capstan turret and engine lathe

A capstan and turret lathes are the development of an engine lathe. The capstan lathe was first developed in the United States of America by Pratt and Whitney in 1860. These types of lathe are the development of an engine lathe so they possess certain basic difference as their construction, operation and use. Let us have a deep insight into the comparison and difference between them. 

Difference :
  • The headstock of a turret lathe is similar to that of an engine lathe in construction but it has a wider range of speeds.
  • Engine lathe required motor of 3 h.p. to drive its spindle and other parts whereas capstan and turret lathe requires high power as 15 h.p. for a high rate of production.
  • The tailstock of and engine lathe is replaced by a turret in turret lathe thus it resembles a big six-sided nut with can carry six tools for rotating jobs on the other side engine lathe holds one tool of limited size.
  • Turret lathe it acts like production machines while engine lathe is used for various types of odd jobs within limits.
  • In a turret lathe, combination cuts can be taken while in centre lathe this type of arrangement is quite uncommon.
  • The labour cost required to operate a capstan and turret lathe is less than that required in centre lathe.
  • Capstan and turret lathe are not usually fitted with lead screws for cutting threads similar to an engine lathe.
  • In capstan and turret lathe one time setting of job then you must not change the tools while in engine lathe you can change tools as per your requirement.
  • Turret movement can be controlled automatically. engine lathe tool movement can control manually. 
  • In capstan and turret lathe number of speeds is more in engine lathe number of speeds is less.
  • Capstan and turret lathe is suitable for mass production while engine lathe is not suitable for that.
  • Capstan and turret lathe tool is centred automatically while an engine lathe tool is centred manually after changing the tool.

Summary : 

An engine lathe is a versatile machine capable of machining any types of jobs with different sizes and shapes. The machine is not suitable for production unit because time is taken to set different tools on the tool post of lathe after each and every operation.
On the other hand capstan and turret lathe is a mass-production machine. They are unsuitable where only one or a few jobs are to be machined. The high initial setting time compared to an engine lathe.