Custom machine shops offer a valuable resource to businesses and individuals within the community they operate in. The skilled craftsmen at machine shops use hand crafting and computer-controlled machines to fabricate replacement parts, customized designs, and perform maintenance and repair on various pieces of equipment from snow blowers to heavy equipment used on farms.
CNC refers to Computer Numerical Control, and is responsible for the automation of machine tools. The types of tools controlled by CNC processes include lathes, drill presses, and screw machines. All of these tools are used in the machining process to cut metal components to desired dimensions with a high degree of accuracy and detail. CNC milling and CNC turning have made it possible to create patterns and add detail to metal components that are not possible by hand. What are the differences between CNC milling and CNC turning?
CNC milling consists of a milling machine that uses commands, or G-codes, programmed into the machine via a computer software program. Each code entered into the program has a designated function that is performed by the machine. When codes are entered into a CNC program representing a potential finished product, the mill then drills and turns along axes to cut and shape the material to match the dimensions entered into the computer.
CNC milling machines are controlled in one of two ways: by computer or via manual override. Computer programming allows the machine to make the precise cuts required, but the manual override allows a CNC machine operator to slow down or speed up or tweak the process if necessary.
There are countless examples of products that can be created using CNC milling processes. Pulleys, arms, linkages, fixtures, and valves are just a few examples of the countless items a CNC machine can replicate. Often customers have a need to make a strong part from aluminum or steel to replace a weak plastic part supplied by the manufacturer.
Turning is a slightly different process compared to CNC milling. CNC turning relies upon computer-controlled machines, but creates a different end product. The process uses a single-point cutting tool that is inserted parallel to the material that will be cut. The material ( metal, plastic, etc.) is rotated at varying speeds and the cutting tool traverses the 2 axis of motion to produce cylindrical cuts with exact depths and diameters.
CNC turning can be used on the outside of material to create a tubular shape, such as a decorative brass shoulder bolt or nautical drive shaft, or it can be used on the inside of material to create a tubular cavity within the chosen material. Just like CNC milling, CNC turning is now an automated process because it can complete projects faster and with greater accuracy than turning a lathe by hand.
As mentioned, CNC turning is used to create objects with round or tubular shapes that are created from larger pieces of material. A drive shaft is a simple example of an object that could be created using CNC turning. Tubing and custom couplings for plumbing or other applications could be created using CNC turning by boring holes into solid materials.
CNC TRAINING & EXPERIENCE REQUIREMENTS
The vast majority of individuals working in a CNC machining shop have completed at least a two-year degree program. Machining degree programs are often offered by specialized tech schools. The curriculum typically includes CNC knowledge-based exercises, video training, and interactive labs with simulators that allow students to engage with replica equipment that helps reinforce key concepts of machining.
Additional educational options vary based upon the specific role an individual exhibits expertise and interest in pursuing. For example, a machine operator is responsible for loading and unloading work pieces, monitoring the machining process, and inspecting finished parts. Machine operators can break into the industry with training from a career technical school or community college.
On the other hand, a CNC manager oversees CNC operations in the shop, handles personnel decisions, and evaluates and upgrades CNC software. CNC managers require management skills, machining knowledge, andprogramming and manufacturing experience. A bachelor’s degree is the minimum requirement for a position as a manager.