Working with metal can involve the utilization of a number of crafts and trades. They may work in separate shops or under the same roof. Metal machining is able to work in both capacities. However, many modern machinists find their employment in a fabrication shop. The latter allows them to perform their skills in a work environment where the next step to their workpiece may actually occur in-house.
A Controlled Subtractive Process
While some manufacturing processes such as welding, are additive, machining is not. It is subtractive. In machining metal, a machinist will remove a little or a substantial amount of metal to produce the desired component. They may have to cut the material down to the correct size or produce a precise shape with exacting internal and/or external diameters. The tools and the techniques reflect this approach. To ensure exactitude, may utilize CNC. The CNC further ensures, the process meets the definition of machining as “controlled” material removal.
Basic Machining Processes
Metal machining uses specific tools. In general, machinists classify their actions into one of the following groups:
1. Drilling: Drill presses are the most common equipment capable of producing the right size and shape holes in the metal. Alternatively, a machinist can employ a lather or a mill to accomplish this
2. Milling: Milling machines, usually under CNC control, are the major tool for this action
3. Turning: Specific turning tools are lathes
However, metal machinists may also bore (thereby improving an existing hole), plane, broach or shape metal workpieces. They may also employ such tools as plasma or laser cutters or EDM for producing specific tolerances in certain metals.
Metal Machining
Machining is a process, a craft, and a learned skill. Unlike several other metalworking skills, it is subtractive. It does not add but takes away undesired or extraneous metal from a piece. In this way, while not an additive process, metal machining does actually add value to a workpiece.
