What is machining?
Metal machining is the process of shaping and cutting metal with different tools and machines. It is versatile and can be used to produce simple or complex components.
The machining process is a key fabrication technique. Machining is a subtractive manufacturing process wherein the metal is removed from the workpiece to create the desired shape.
In this blog, we will discuss different machining processes, the materials used in metal machining, and why you should consider fabrication as a service for your machining operations.
Types of Metal Machining Processes
Turning is a machining technique that uses a lathe to rotate the metal while a cutting tool cuts and removes material along the diameter to create a cylindrical shape. It is considered a basic machining job.
The machinist can produce different workpieces by orienting the cutting tool in different directions, using a traditional lathe machine (requiring constant supervision), or an automated lathe. Today, CNC lathe machines, or computer numerically controlled machines, have become popular.
Generally, turning produces rotational and axis-symmetric parts. Skilled mechanists use turning to create various features, including holes, groves, threads, diameter steps, and curved surfaces, and can produce entire workpieces by turning.
Use cases for turning
Precision turning is used to fabricate shafts, crankshafts, camshafts, bowls, valves, gears, furniture components, and threaded fasteners. This versatile machining process is widely employed in various industries to create a wide range of components with precise dimensions, smooth surfaces, and intricate details.
Milling is a machining technique using multi-point cutting tools to remove material from the workpiece. In CNC milling, the workpiece is typically fed to the cutting tool in the same plane as the rotation of the cutting tool. In manual milling, however, the machine feeds the workpiece in the opposite direction of the cutting tool.
The milling machines can be vertically or horizontally oriented. A basic milling machine has three-axis movements, and more advanced models have additional axes.
Use cases of milling
Fabricators use milling to manufacture gears, create slots or grooves in workpieces, create flat and uneven surfaces, and create complex shapes.
Drilling is the process of producing cylindrical holes in solid material with drill bits. Drill bits are rotatory cutting tools used to create cylindrical holes, usually in the cross-section of metal workpieces. It is one of the most widely used machining process types.
The size of the drill bit determines the size of the hole in the workpiece. Drill bits can make holes in various materials and come in different sizes and forms, from small hand-held bits to large industrial bits. Machinists attach drill bits to a drill machine, which rotates and provides the required torque and axial forces to create holes.
The operator presses the bit against the workpiece and rotates it rapidly, between hundreds and thousands of revolutions per minute. This forces the bits to cut off chips from the drill. The rotation rate of the drill bits depends on several factors, like the material and the hole size.
Drilling is a simple process consisting of rotating the drill and feeding it into the workpiece. The machinist adjusts the drill’s cutting speed and feed rate. Common drilling techniques include tapping, countersinking, reaming, counterboring, and spot-facing.
Drilling uses it to create holes on different surfaces and pivot holes for screws, threads for nuts, and countersinks.
Use cases for drilling
Drilling is used to create precise cylindrical holes in various materials, essential for applications like fastener installation and component assembly.
Grinding is a machining process that uses a grinding wheel to remove material from a workpiece. As the grinding wheel rotates, it removes material from the workpiece, creating a smooth surface texture.
Grinding operates on a simple principle a rotating tool with an abrasive grain works on the workpiece to remove material. You can think of each abrasive grain as a cutting tool.
We can classify commercial grinding into:
- Rough grinding maximizes the metal removed at the cost of surface finish. The surface finish of a rough-ground workpiece is typically in the range of 10 to 100 microinches.
- Finishing grinding produces a much smoother surface finish, in the range of 0.1 to 1 microinch.
- Precision grinding is the middle ground between metal removal and part size control. It lays the groundwork for creep feed grinding, slot grinding, and high-efficiency deep grinding.
- Ultra-precision grinding does not involve actual grinding but a sliding action with very fine grains to create a high finish.
Use cases for grinding
Machinists use grinders to remove material from various surfaces, like metal, wood, and plastic. It is a precise process that can create smooth surfaces with tight tolerances. Technicians utilize on-site grinding for repair and maintenance tasks, while machinists employ machine shop grinding for finishing operations.
Advanced Metal Machining Techniques
Advanced metal machining has changed the way we transform workpieces into intricate and precise components. These processes have improved the speed and accuracy of machining. It has made it possible to create complex components that were impossible before.
Computer Numerical Control (CNC) machining
Computer numerical control (CNC) is a manufacturing method where machine tools can move precisely thanks to embedded, preprogrammed computer software.
Fabricators use CNC machines to manufacture machine parts made of metal and plastic.
CNC can also automate cutting equipment, including mills, lathes, routers, drills, grinders, water jets, and lasers. It can control machinery tools like welding, electronic assembly, and filament winding equipment.
G-Code and M-Code control the CNC machine. M-code manages non-moving tasks, and G-code governs how the CNC machine moves and performs.
The advantages of CNC machines are:
- Precision: Use CNC machines to create parts with high tolerance.
- Cost reduction: CNC machines can reduce waste because of their precision. Energy consumption is reduced due to higher productivity, scalability, and less material waste.
- Waste reduction: The software running the CNC machines uses simulation and optimization exercises, resulting in little to no waste during production.
- Complexity: You can use CNC machines to manufacture complex parts.
- Reduced human error: CNC offers better precision, speed, flexibility, and reproducibility by eliminating human error from the manufacturing process.
Use cases of CNC machines
Some applications of CNC machining include precision machining, prototype and rapid manufacturing, mass production, woodwork and furniture manufacturing, metal fabrication, and electronic and PCB manufacturing.
Electric Discharge Machine (EDM)
An electronic discharge machine (EDM) or spark machine is a metal fabrication process that uses a spark to obtain the desired shape. Rapid current discharge between the electrodes removes the material, and the dielectric fluid acts as an electric insulating fluid to separate the two electrodes.
The workpiece operates as an electrode and must be a good conductor of electricity. A high-voltage spark is applied between the electrode and the workpiece. The spark erodes the workpiece.
The workpiece acts as the anode, and the tool acts as the cathode in this process. A controlled spark helps in the processing of the workpiece. The dielectric fluid flushes the debris away and helps control the temperature and electrical spark during the machining.
The advantages of EDM are
- Suitable for different materials: EDM can work effectively on various materials, as long as the material is a good conductor of electricity. You can machine materials made from tungsten or titanium. You can use EDM to work on hardened material.
- Mechanical force is not required. Since no mechanical force is involved, you do not have to worry about fragile outlines or mechanical stress.
- Enables various shapes: You can use EDM to cut unconventional shapes that are impossible with conventional machines.
Applications of EDM include injection moulding, small-hole drilling, and die casting.
Fabrication as a Service
Fabrication as a service is a new business model where clients looking for fabricators to build their custom products have a platform to connect with fabricators with the skill and expertise to meet their requirements. Venwiz is India’s leading FAAS platform, with over 3,000 vendor profiles in its database. Venwiz allows clients to post detailed project requirements. Vendors can bid on the project, and clients can choose the vendor that is the best fit. Alternatively, the client can scan the extensive database and shortlist vendors based on experience, clients, turnover, and certifications.
How do I choose a FAAS vendor?
If you are considering a FAAS vendor, you must choose a reputable vendor with a proven track record. Our tips for selecting a FAAS vendor:
- Define your requirements: Start by defining your requirements. Know the scope of work, the MOC, the timeline, the budget, and whether you have on-site or shop machining. It will be easier to narrow your options once you answer these questions.
- Experience: Don’t just focus on the vendor’s experience; look at the projects they have managed. Your business is unlikely to benefit from engaging a company that has no experience with projects similar to yours.
- Quality: Irrespective of whether the project is big or small, you cannot compromise on quality. Your equipment must meet the quality specifications of regulatory authorities and any internal quality checks you may have. Ensure the company has the testing tools and quality assurance plans to meet the required quality standards.
- Competitive prices: Hire a vendor that offers competitive prices. We recommend you take quotes from multiple vendors to get a fair market price
- Reviews – Read online reviews to learn about quality and customer service. Venwiz provides reviews of all the vendors listed on its website.
- Financial stability: The financial stability of the fabrication vendor is important. You can compare the turnover of different vendors on Venwiz. The platform offers financial services as well.
Some of our leading vendors providing FAAS Services are:
Hi-Tech CNC Technology is an ISO 9001:2015-certified manufacturer and supplier, specializing in precision components. Our services include the design, manufacture, and supply of a range of essential components, including boring bar tools, rock drilling tools, tool jig fixtures, stainless steel rings, boring tools, insert rings, and machined roll rings. with a dedicated team, advanced machinery, and a focus on quality.
Camtronix has a strong presence in Karnataka. Our company, an AS 9100D and ISO 9001:2015 certified manufacturer, excels in producing a wide range of precision components for the equipment industry. Their services encompass precision CNC milling, press tools, sheet metal components, and the manufacturing of CNC machine components, jigs, and fixtures.
With over a decade of expertise in precision machining, Mahasvin Technologies is a leading name in the field of manufacturing jigs, fixtures, and precision components for the aerospace industry. Their capabilities encompass design and engineering using Fusion 360, Power Mill, and Mastercam to develop NC programs, as well as CAD for 2D drawings. They specialize in new developments and prototypes for sheet metal and precision-machined components in automotive, defense, and aerospace applications.
Metal machining is a complex process, and you need to consider several factors before you start machining. Venwiz has skilled vendors who can meet your requirements for producing precise machine parts with high tolerances. Visit us at Venwiz to explore our FAAS vendors.
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