Machining
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Conventional Machining, one of the most important material removal methods, is a collection of material-working processes in which power-driven machine tools, such as lathes, milling machines, and drill presses are used with a sharp cutting tool to mechanically cut the material to achieve the desired geometry. Machining is a part of the manufacture of almost all metal products. It is not uncommon for other materials to be machined.
Machining is advantageous to processes like molding and casting in terms of required setup time and cost, and as such is often used in a prototyping capacity.
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[edit] Processes
Machining principally consists of three basic cutting operations:
- Turning performed on a Lathe, which makes the raduis of the metal smaller
- Milling performed on a Mill, using various cutting tools
- Drilling on various machines, primarily Drill Presses
[edit] Turning
[edit] Chucks and Faceplates
Lathe chucks are used greatly for holding what is going to be machined. There are two types of chucks, an indepentent chuck or the universal chuck.
[edit] Tooling
[edit] Milling
[edit] Workholding
[edit] Cutting tools
[edit] End Mills
[edit] Face Mill
[edit] Process
[edit] Convention vs. Climb Milling
[edit] Drilling
[edit] Other Processes
[edit] Boring
[edit] Sawing
[edit] Grinding
[edit] Scraping
[edit] Broaching
[edit] Planing
[edit] Theory
Because machining is not a single process but a group of processes, no single principle is applicable to every aspect of machining. However, all machining processes do have in common the removal of chips or "swarf" by the relative motion of a cutting tool against the workpiece or part. The means by which this motion is achieved varies by machine type, but can generally be broken down into two types of motion:
Primary motion is the result of a machine tool's speed. In the case of a simple drilling operation, this is the spinning of the drill bit. A secondary motion is provided by a tools feed. In the example of a drilling operation, this is the plunging of the drill bit into the material.
Determining optimal speeds and feeds is a major component of best machining practices. A huge number of variables are factors in determining these properties: materials of both workpiece and cutting tool, geometry of the cut, the coolant or cutting fluid used, finish and tolerance required, and the rigidity and power of the machine tool being used.
