In the previous blog posts, we have discussed two of the most versatile machining tools used anywhere from a home based machine shop to a large size heavy duty mechanical complex: Lathe and Milling. In the current post, a comprehensive comparison between the two tools will be presented.
Without pretense, it is asserted that there are certainly some similarities between the two machining tools despite several differences.
Both machining tools perform machining operations on metals, non-metals as well as woods and composites. Both use cutting tools for machining desired geometry on the work and have equivalent machining precision and accuracy when properly set up and arranged.
Moreover, the two are subtractive manufacturing machines that can perform multiple machining operations and use almost similar work holding supports such as chuck, collet, vises, fixtures, and other clamping means. Lastly, both are available in CNC versions that use programming language based on G and M codes.
However, there can be drawn multiple differences between the two tools which can be indexed upon the factors as cited in the figure below.
Difference Between Lathe and Milling Machine
Difference based on cutting operation
A lathe is chiefly used to perform turning operations on the workpart cylindrical in geometry. Whereas, a milling machine is extensively used to remove material from the flat, contoured, and irregular surfaces.
Difference based on cutting tool
Lathe uses a single-point cutting tool (such as a turning tool or boring tool) to perform machining operations compared to a milling machine that uses a multi-edge tool known as a milling cutter (such as end mills, or slot drills) for milling large flat surfaces.
Difference based on cutting operation
In a lathe workpart rotates while a linear feed is provided to the cutting tool. In a mill, the milling cutter rotates and travels in a direction perpendicular to the flat workpiece.
Difference based on feed direction
In lathes, a two-directional feed is provided to the cutting tool (longitudinally and crosswise. But, in milling machines, the milling cutter is fed to move along three axes.
Difference based on workpart geometry
A lathe is used to machine parts with cylindrical and tapered geometry, whereas, milling machines are popular in machining a variety of part configurations from simple flat surfaces to the intricate 3D geometries.
Difference based on design
Lathe machine is famously designed in a horizontal configuration, though its vertical-design arrangement is also available. While on the contrary, the milling machine is mostly constructed in a vertically oriented setting yet its horizontal version is also used commercially for performing key milling operations.
Differences based on applications
Lathe is a perfect machining choice for producing parts such as shafts, pins, bushings, screws, nozzles, and so on. On the other hand, mills produce a diverse range of industrial products such as dies and mold plates, tooling, as well as parts used in the aerospace and automobile industry.
Differences based on chatter and vibration
The machining operations on the lathe are without or negligible noise and vibration as the workpiece is firmly clamped in the 3-jaw or 4-jaw chuck. On the contrary, in the milling machine part, rattling as well as platform vibrations can be observed without difficulty due to the large surface area of the work and somewhat comparatively less secure means for fastening.
Differences based on chip size
Lathe cuts the workpart surface in a somewhat uninterrupted way, thereby producing continuous chips in a spiral fashion. Whereas, in the case of a milling machine, the chip size varies from operation to operation and is chiefly smaller in size yet more in thickness.
Difference based on foot-print and cost
Lathes are relatively smaller in size and are less expensive compared to their milling counterparts which occupy more square inches and are costlier.
I am the author of Mechanical Mentor. Graduated in mechanical engineering from University of Engineering and Technology (UET), I currently hold a senior position in one of the largest manufacturers of home appliances in the country: Pak Elektron Limited (PEL).