Even simple products like shafts or fasteners require multiple machining operations, from milling to surface finishing. As complexity increases, more machining operations and equipment are necessary to shape the workpiece. Meanwhile, a CNC machine shop is a space or factory that contains all the equipment and arrangements to handle all subtractive manufacturing designs.
Furthermore, this article will uncover the different machinery & safety protocols in a machining shop. We will also examine the advantages, applications, challenges, and how you can choose the best shop for your manufacturing project at the end.
What Is a CNC Machine Shop?
First, let’s understand its basic concept: What is a machine shop? It is a confined space with various manufacturing equipment, machinery, tools, workforce, and other essential things to convert any design into a physical item. The term ” machine shop” is for the subtractive manufacturing facility, which involves various advanced and CNC-controlled systems and machines, from a CNC mill to a drill press and inspection equipment like a CMM machine.
The main goal of this manufacturing shop is to provide machining services for a wide range of industries based on their designs and production requirements. It can produce diverse parts & production, whether it is a prototyping project for a startup or large-scale runs for an established business. So, product developers can excel in their ideas in the market or produce their existing products without their own CNC machining factory.
The Role of CNC Machine Shops in Different Industries
Do you know how many manufacturers supply the parts for a single aircraft? Many specialized CNC machining shops produce some specific components. For example, one shop might work on turbofan blades, while another can make the fuel nozzles:
So, different industries rely on separate manufacturing partners to outsource the required components.
| Industry | Role of CNC Machine Shops | Application Examples |
| Automotive | High-tolerance parts for reliability and performance. | Engine blocks, gears cylinder pistons, brake discs, camshafts, etc. |
| Medical Equipment | Equipment’s components and bio-compatible implants. | Surgical instruments, dental fixtures, implants, joint replacements, bone screws, and more. |
| Aerospace and Defense | Aerospace parts that meet standards for strength, precision, and lightweight. | Fuselage panels, landing gear components, cockpit instruments, satellite components, etc. |
| Electronics & Semiconductor | Micro-level precision | Microchips, connectors, electronic enclosures, circuit boards, etc. |
| Marine | Durable & corrosion-resistant parts for marine vessels | Shafts, housings, deck equipment, valve components, drive shafts, etc. |
| Energy (Oil & Gas, Renewable) | High-performance parts | Drill bits, solar panel frames, piping systems, valves, etc. |
Types of CNC Machines in a CNC Machine Shop
The CNC equipment is what makes a space a machining workshop. Manufacturers installed and set the various equipment and mechanisms to handle the expected machining tasks. Meanwhile, most of the machines in such shops shape the workpiece by removing the material from the outer surface using cutting tools.
Although each shop might have different machines according to their CNC machining business model, they commonly include the following CNC machines;
- Milling Machine
- Lathe
- Machining Center
- Grinding Machine
- Drill Press
- Bandsaw
- EDM Machine
- Inspection Equipment
1. Milling Machine
A CNC Mill or milling machine can handle different materials to shape them according to the designed geometry. The machine could have 3, 4, 5, or even more axes movement ability. Typically, the work table moves along the X and Y-axis, carrying the workpiece to the proper position. Meanwhile, the spindle holds the cutting tools and moves along the Z-axis for vertical cutting operations. Here, table movement also controls the feeding against the rotating milling tool.
This machine is ideal for shapes with flat surfaces. However, it can also make complex geometries with the use of respective tools & operations like CNC milling, drilling, slotting, profile milling, thread milling, etc. However, drilling can be separately done by a drill press or CNC drilling machine. Here you can read the differences between CNC milling vs. Drilling.
2. Lathe
In contrast to a mill, a lathe machine removes the material by feeding the tool into a rotating workpiece. Here, the work rotates symmetrically( around its center). So, lathe operations are valuable in cylindrical & conical parts manufacturing.
During the lathe machining, the spindle( tool) moves across the workpiece and removes the material. At the same time, the Chuck holding the work can be adjusted to align the positioning with the tool.
Furthermore, a CNC lathe machine can execute the CNC turning, cutting, facing, knurling, and other operations with proper tooling.
3. Machining Center
It is the advanced version of the milling machine with more production and complexity handling advantages. The main difference with other CNC equipment is its diverse capability of CNC machining, including milling, drilling, and tapping. Next, the Machining Center also contains an automatic tool-changing mechanism that reduces the setup time and performs multiple operations seamlessly on the work material.
Two types of machining centers can be found in the manufacturing industry based on the spindle orientation;
- Horizontal Machining Centre
- Vertical Machining Centre(VMC)
Moreover, the universal type of CNC machining center can move its spindle in both directions to tackle the complex features and details.
4. Grinding Machine
The role of a grinding machine in a CNC machining shop is to customize the machined surface of parts to the intended level of dimensions and finish. It removes the burrs, attached chips, and cutting marks using an abrasive wheel.
When the spinning wheel with abrasive on the surface comes in contact with the surface of the machined parts, it cuts the excess or attached material and leaves a smooth surface.
The grinding process can fix minor dimensional inaccuracies of components and achieve a mirror-like finish (Ra 0.02 μm). The thing is, the result depends on the type of abrasive material and feeding control.
Furthermore, the perfect combination of material type and grit number of the abrasive wheel is essential to achieve the desired Ra value. The grit number refers to the coarseness or fineness of the abrasive particles used on the wheel.
- Low Grit (10-24): These are suitable for rapid material removal and roughing.
- Medium Grit (30-60): Balanced for moderate material removal; typical in general fabrication.
- Fine Grit (80-120): For finer surface finishes and lower material removal; used in finishing operations.
- Very Fine Grit (150-600): Provides very smooth finishes; suitable for precision tasks and delicate surfaces.
5. Drill Press
This machine is known for precise and deep-hole drilling. It contains a drill tool mounted on the press. Meanwhile, the press can have a mechanical, hydraulic, or automatic mechanism. Once the drill tip touches the surface, the connected motor system rotates the drill to penetrate it into the material.
Here, the operator can control the down-feed pressure of drill edges into workpieces or with the automatic control systems. It can drill holes faster and more easily than CNC drilling.
6. Bandsaw
Large bars, blocks, or sheets cannot be processed directly with CNC machines or other fabrication equipment. Instead, they are required to be cut into appropriate sizes before shaping. Thus, the bend saw in the CNC machine shop is known for straight & curved cuts into the workpiece and cutting the work material into small pieces.
The working of a bandsaw involves applying long flexible blades into the cutting position front & back. In the return stroke, blade edges exert force and throw away the material to form a desired cut.
7. EDM Machine
The Precision CNC Machine Shop also needs an Electrical Discharge machining setup to manipulate the hard materials and intricate geometries. It is compatible with extremely hard materials like titanium and tool steel.
- Complex or intricate shapes
- Sharp corners
- Undercuts
- Cavities with fine details
- Diverse Patterns
- Micro-machining
- Gear profiles
The material removal takes place with an electrical discharge on the work metal that forms when the electrode touches the workpiece. Meanwhile, both the workpiece and cutting tool (electrode) remain in the dielectric fluid.
The EDM machine produces intense heat during machining, which melts the machining area precisely to create the designed geometry. Subsequently, it is only workable for the conductive metals as they can only create electrical discharges.
8. Inspection Equipment
The quality control process ensures that machining services meet the specifications and requirements stated in the design. Therefore, every prototype and production machine shop includes various inspection equipment to monitor the production process and verify the dimensions, tolerances, features, roughness level, etc.
Here are some typical inspection equipment & tools;
- Coordinate Measuring Machine (CMM)
- Micrometers and Gauges
- Optical Comparators
- Laser Scanners
- Rockwell Hardness Tester
The CMM machine is a highly preferred inspection machine across the machining shops. It measures different geometric dimensions & accuracies, alignments, surface contours, feature locations, etc.
Manual vs Automated Machining
The features and speed of automated machining outdo the manual machining capabilities. Since the CNC system can work with minimal human intervention, it increases accuracy & precision. Moreover, CNC machines can perform multiple operations with ATC mechanisms. Also, there is higher safety than manual ones.
Let’s look at the following comparison table for specific differences between Manual vs. Automated machining;
| Aspect | Manual Machining | Automated Machining |
| Precision | It depends on the operator’s skill and experience. Anyway, less precise than Automated. | Automation achieves high precision and exact specifications, as low as s ±0.0025mm. |
| Consistency | Each part may differ slightly | Uniform results across all batches. |
| Speed | Tme-intensive and Slower process | High production speeds due to continuous operations and rapid machine movements. |
| Labor Skill Level | Highly skilled operators with comprehensive knowledge of machinery | Skilled in setup and running the process, but simply monitoring and adjusting settings. |
| Cost Efficiency | Cost-effective for lower volumes | Significantly economical over the long term for high-volume productions. |
| Flexibility | It facilitates quick changes in tooling and designs. | Less flexible because of software adjustment requirements. |
Advantages of Utilizing a CNC Machine Shop
Each of the industries we discuss above has several benefits from collaboration with a CNC machine shop. It gives the opportunities to businesses to manufacture their design without significant investment in the machining & CNC tooling setup. They can simply send the design to machine shops anywhere around the world and can get the part ready at the door.
The primary advantages are;
High Precision and Consistency
The CNC machines and tooling in a CNC shop produce precise and consistent products, regardless of production volume. The computer control mechanism guides the tools to accurately remove the material.
However, the precision might depend on cnc machining capabilities of a particular machining workshop. This means precision is determined by shops that have lower or higher axes machines (3, 4, 5, or even higher taxes machines).
Production Speed & Efficiency
The automatic control of machining processes and minimal human intervention speed up the production cycles. Additionally, the CNC equipment can operate 24/7 with proper maintenance and care.
The high production speed reduces the lead times and costs. Typically, CNC is 3 to 5 times faster than conventional machines.
Cost-effective Production
The tool path optimization in CNC machining lowers the material waste and machine setup time. Consequently, minimal human intervention reduces the time also. All these reasons make CNC a highly cost-effective method, from prototyping to mass production.
Complexity and Flexibility
The tooling adjustment can process almost every type of design with a single setup. As a result, CNC shops can machine complex geometries, like irregular profiles, deep cavities, and surface detailing.
Next, the manufacturer can quickly change their designs with minimal cost and time to optimize the production quality. It also supports customization and innovation.
Common Challenges Faced by CNC Machine Shops
Like other technologies, CNC machine shops are not free of limitations or challenges. Here are some technological, operational, and economic challenges associated with it;
1. High Upfront Investment
Not only the CNC machines and other manufacturing equipment but the cost of quality control tools, electrical arrangement, tooling, and space is also significant for a CNC shop than conventional setups. However, the long-term use of these machines and tools contributes to the lower per-unit cost.
2. Rapid Technological Advancements
We are at a time, where every day new technologies are coming regarding machineries, process monitoring, and tooling. Sometimes, the shop owner might struggle to adapt due to a lack of expertise and investment. For Example:
If a shop integrated an electronic monitoring system one year ago, now the same shop needs to update it with AI integration to be competitive in the market.
3. Operational & Maintenance Challenges
First, skilled and expert operators can only execute the machining tasks. So, it is challenging to find such skilled manpower that can learn and adapt to the new advancements.
Next, the maintenance cost for CNC systems and machine components is also high because of complexity, required precision level, and regular software updates.
4. Workshop Saftey
The workers, machinery, and even environmental safety are crucial for a workshop. At the same time, planning & execution of safety rules and principles is challenging because it demands frequent training, continuous customization of safety equipment, routine inspection, machine maintenance, and consideration of environmental impacts.
CNC Machine Shop Safety Rules to Follow
Shop safety practices are not only about an operator wearing PPE in the machining factory. Moreover, it entails identifying and correcting the potential risks before any damage. Therefore, setting and following the CNC machine shop safety rules is essential for the shop’s operation.
Let’s elaborate on the three major safety rules in brief;
1. Personal Protective Equipment (PPE)
It refers to protective gear like helmets, earmuffs, shoes, goggles, and related clothing designed to safeguard the operator or any other professional in the CNC shop from physical hazards. Consequently, what kind of PPE is determined by the specific job he/she handles or the potential risks associated with that.
2. Machine Operation Safety
Any faults in machines, tools, and, alignment can cause a risk to the overall shop’s safety. So, the operators should be well-trained and knowledgeable about the machinery and possible errors during the machine’s operation.
Next, the machine itself should be fit and safe to execute the machining process. The digital monitoring systems track the tool wear, machine health, and performance metrics to predict the risk and required maintenance.
3. Material Handling Safety
The sharp edges of material can cause injuries in a lack of proper material handling. Consequently, other similar risks are associated with material & product management. Thus, following the safety rules for material handling is absolutely necessary.
This safety measure focuses on training workers and adopting handling tools and mechanisms like conveyors and forklifts.
How to Select the Right CNC Machine Shop?
The only right machining workshop according to your requirements can eliminate the burden of installing a CNC factory to manufacture your designs and product ideas. Therefore, many considerations are necessary while selecting the CNC shop, such as available machinery, precision capabilities, project timeline, cost, etc.
1. Capabilities and Services Offered
First and foremost, does the shop have the equipment and tools to handle your design? You need to consider 3, 4, or 4-axis CNC machines, what level of tolerance the machine can achieve, available material options, surface finish, and more.
Next, look for the services they offer. It could be what machining processes they offer ( milling, drilling, turning, etc.) or industries they are supplying parts for.
2. Competitive Pricing
The price of the same project or design differs from one to another shop. Meanwhile, your project specifications like size, precision, timeline, and material also influence the cost. Here, the goal is to find the perfect balance of quality and cost. But, you cannot compromise the features and functionality of the intended item.
The best way to find a cost-effective shop is to request detailed quotes for your design from different shops and analyze their offering and costs.
3. Production Capacity and Scalability
Another factor is the capacity and scalability option of the CNC machining shop, what volumes can the shop deliver in a specific timeframe? If you just need some prototypes or small batches, can the factory or shop extend the production with reasonable cost & time in the future?
4. Experience and Expertise
It is the primary requirement that the shop you are going to partner with must have a similar experience. Only that, you can ensure they can handle the task to the specifications without any error. For example, if you need to machine aircraft engine components, the shop must have experience working with several clients from the aerospace industry.
5. Quality Control and Certifications
The certification is extra important, especially for applications that require certain standards to fulfill like medical and aerospace parts. To ensure that potential collaborator has rigorous quality control, you can check their certification like ISO, CEN, FDA-approved material, etc.
Choose Your CNC Machine Shop
As cost & precision are crucial factors of any CNC service, you can choose a manufacturing center in China for your current or upcoming project. The vast network of material chains and manufacturing infrastructures makes China the best destination to outsource the machining parts and products.
The low labor cost, government subsidies, expert professionals, heavy R&D, and reliable logistic allows Chinese firms to offer way lower costs than US & Europe-based companies.
RapidDirect is a China-based manufacturing service provider with over a decade of experience producing parts & products for numerous industries across the world. We have our own machining factory with 3,4,5-axis milling, turning, EDM machine, inspection equipment, and surface finishing facilities.
Furthermore, we are flexible with the volume of production and further scalability. We are ready to help your business, so send us your design for an accurate & detailed quote.
Conclusion
Overall, manufacturing all components in own factory is not feasible and beneficial for companies in a current fast-paced market. Therefore, industries take benefit from the cumulative experience of various CNC machine shops to manufacture the components and end products. Instead of working on how to start a machine shop, they can focus on design and innovations to be ahead in the market. Meanwhile, external manufacturers like RapidDirect can work for those companies to create high-standard parts at less cost.
