Types of lathe machine

The four main types of lathes are

1.Speed Lathes

After completing this unit, you should be able to:

• Describe the Speed, Feed, and Depth of cut.

Speed, feed, and depth of cut are three important factors that determine the efficiency and quality of a machining operation.

1. Speed (also known as cutting speed or spindle speed) refers to the rotational speed of the cutting tool, measured in revolutions per minute (RPM).

2. Feed rate refers to the linear speed at which the cutting tool moves into the workpiece, measured in inches per minute (IPM) or millimeters per minute (mm/min).

3. Depth of cut refers to the distance that the cutting tool penetrates into the workpiece, measured in inches (in) or millimeters (mm).

Optimal values for speed, feed, and depth of cut are dependent on the specific material being machined, the type of cutting tool used, and the desired result.

• Determine the RPM for different materials and diameters.

The RPM for a given machining operation depends on various factors, including the material being machined, the diameter of the tool, and the desired surface finish and cutting speed.

As a general rule, the RPM for a given diameter of cutting tool decreases as the hardness of the material increases. The following is a rough guide for determining RPM based on material type:

.Soft materials (e.g., aluminum, brass, plastic): 800-10,000 RPM

Medium-hard materials (e.g., steel, cast iron): 400-800 RPM

Hard materials (e.g., high-speed steel, hardened steel): 100-400 RPM

The diameter of the tool also plays a role in determining the RPM. In general, as the diameter of the tool increases, the RPM should be reduced to prevent tool breakage and to ensure a proper cutting speed.

It is important to note that these are general guidelines and that the optimal RPM for a given operation may vary. It is always recommended to consult with a machining expert or to use cutting speed calculators for specific recommendations for a given material and tool diameter.

• Describe the federate for turning.

Feed rate in turning refers to the linear speed at which the cutting tool moves into the workpiece while rotating. The feed rate is usually expressed in inches per minute (IPM) or millimeters per minute (mm/min).

The feed rate in turning has a significant impact on the efficiency and quality of the machining operation. A too-slow feed rate can lead to a longer cycle time and a poor surface finish, while a too-fast feed rate can cause excessive tool wear, tool breakage, or reduced accuracy.

The optimal feed rate for a given turning operation depends on various factors, including the material being machined, the diameter of the tool, the speed of the tool, and the desired surface finish.

It is important to use the correct feed rate for a given turning operation to ensure efficient machining and high-quality results. It is always recommended to consult with a machining expert or to use cutting speed calculators for specific recommendations for a given material and tool diameter .

• Describe the setting speed.

The setting speed in machining refers to the speed at which the cutting tool is set into the workpiece. The setting speed is usually expressed in inches per minute (IPM) or millimeters per minute (mm/min).

The setting speed is important because it affects the accuracy of the machined part, the cutting speed, and the surface finish. A too-slow setting speed can cause excessive tool wear, while a too-fast setting speed can cause tool breakage or reduced accuracy.

The optimal setting speed for a given machining operation depends on various factors, including the material being machined, the diameter of the tool, the speed of the tool, and the desired surface finish.

In general, the setting speed should be adjusted based on the cutting speed and the material being machined to ensure efficient machining and high-quality results. It is always recommended to consult with a machining expert or to use cutting speed calculators for specific recommendations for a given material and tool diameter.

• Describe the setting feed.

To operate any machine efficiently, the machinist must learn the importance of cutting speeds and feeds. A lot of time can be lost if the machines are not set at the proper speed and feeds for the workpiece.

In order to eliminate this time loss, we can, and should, use recommended metal-removal rates that have been researched and tested by steel and cutting-tool manufactures. We can find these cutting speeds and metal removal rates in our appendix or in the Machinery’s.

We can control the feed on an engine lathe by using the change gears in the quick-change gearbox. Our textbook recommends whenever possible, only two cuts should be taken to bring a diameter to size: a roughing cut and a finishing cut.

It has been my experience to take at least three cuts. One to remove excess material quickly: the rough cut, one cut to establish finish and to allow for tool pressure, and one to finish the cut.

If you were cutting thread all day long: day in and day out. You might set the lathe up for only two cuts. One cut to remove all but .002 or .003 of material and the last cut to hold size and finish. This is done all the time in some shops today.

Have you noticed that when you take a very small cut on the lathe .001 to .002 that the finish is usually poor, and that on the rough cut you made prior to this very light cut, the finish was good? The reason for this is: some tool pressure is desirable when making finish cuts.

2.Engine Lathes : Romi T-

Universal lathes from Line ROMI T were carefully designed for offering total safety for the operator, according standard NR-12.

They are safe, versatile, reliable machines, ideal for tooling, maintenance and teaching work, due to the variety of optional available, for setting the machine according the need of application.

A very large variety of combinations of pitches and infeeds is possible to be obtained, due to its set design. Over and above, by changing only one gear in turn over, it is possible to obtain two settings of threads: one for metric thread and inches, other for module thread and Diametral Pitch.

3.Tool Room Lathes : 

Graded Casting with Hardened & Ground Guide waysHardened & Ground Spindle and Gears in HeadstockCam lock Spindle Nose is standardUniversal Feed Box of toughened EN-8 material with inch, mm, DP and Module threadGap Bed is standard.
  Accuracy-
As per IS Standard 1878 (Part-I)


Work piece on Chuck (Turning)-Roundness of 0.01mm taper near headstockWork piece between Centers (Facing) Flatness of 0.02mm/ 300mm length in concave direction. 
 Accessories-

Self Centering Chuck, Independent Jaws Chuck, Steady Rest, Follow Rest, Revolving Center, Digital Read Out, Taper Turning Attachment, Grinding Attachment, Electromagnetic Footbrake, Milling Attachment

4.Turret Lathes : 

Turret lathes are a type of metalworking lathe that are designed for high-volume production and efficient machining of cylindrical parts. They are named for the turret that is mounted on the top of the bed, which holds a series of cutting tools and allows for quick tool changes.

Turret lathes typically have a headstock, tailstock, and a bed, as well as a cross slide and a turret. They also typically have a leadscrew, a feed rod, and a carriage that moves along the bed to control the cutting tool's position.

Advantages of turret lathes include their ability to perform multiple operations in a single setup, the quick tool change capability, and their suitability for high-volume production. They are commonly used in industries such as automotive, aerospace, and electrical components.

It is important to properly set up and operate turret lathes to ensure efficient machining and high-quality results. This may include properly aligning the tool holders, properly tightening the tool clamps, and ensuring that the correct cutting speed and feed rate are used for the given operation

The turret lathe is a form of metalworking lathe that is used for repetitive production of duplicate parts, which by the nature of their cutting process are usually interchangeable. It evolved from earlier lathes with the addition of the turret, which is an indexable tool holder  that allows multiple cutting operations to be performed, each with a different cutting tool, in easy, rapid succession, with no need for the operator to perform setup tasks in between, such as installing or uninstalling tools, nor to control the tool path. The latter is due to the tool path's being controlled by the machine, either in jig-like like fashion, via the mechanical limits placed on it by the turret's slide and stops, or via electronically-directed directed servomechanisms for computer numerical control lathes.

                       Hartness turret Lath