Machining Services

CNC Machining Capabilities

Sinclair & Sons Custom Welding & Machine Service is an AS9100D and ISO 9001:2015 Registered manufacturer of custom metal components. Our skilled machinists use the latest equipment and manufacturing techniques to create precision components of unsurpassed quality.

Our specific machining capabilities include:

  • Conventional milling
  • CNC milling
  • CNC lathe
  • Big blocks
  • Small blocks

Computer numerical control, or CNC, has made it fast, efficient, and affordable to machine complex parts. The term refers to any manufacturing process in which a computer guides automated cutting tools to machine stock. Typically, this type of automation is used with mills and lathes, allowing the material to be removed rapidly and precisely.

CNC stations differ depending on the number, type, and position of the machining parts. For instance, the workpiece is stationary in some machines while the tool moves along 2 or 3 axes. In others, the tool remains in place while the workpiece rotates and moves. More complex stations allow the workpiece and the tool to move in tandem, facilitating more complicated cuts and features.

As a full-service metal parts provider, Sinclair & Sons combines CNC with conventional machining to create the most precise components possible.

CNC Milling

Sinclair & Sons is a leading machining service provider, delivering quality results through our various techniques and services. One of our main machining methods is CNC milling, allowing us to produce small and large parts and components with extreme accuracy. Regardless of its stringent tolerances and intricate features, we can mass-produce complex pieces with high precision and repeatability.

Milling is one of the most common and versatile CNC processes. In CNC milling, one or more cutting tools progressively remove material from a workpiece to yield the final geometry. Because a computer controls the cutting tools, their movements are remarkably precise, allowing CNC mills to achieve extremely tight tolerances regardless of complexity.

CNC mills typically perform three millings. In 3-axis milling, the workpiece is stationary while the cutting tool moves along the X, Y, and Z axes. This process is most appropriate for machining features on a single plane of the workpiece.

Both types of CNC mills can handle different sizes and materials, including a full range of wood, metal, and plastic workpieces. Some common materials include:

CNC Machining Services Infographic


  • Aluminum
  • Stainless steel
  • Steel
  • Copper/Brass

This versatility means that CNC milling can be useful wherever tight tolerances are required. It includes applications such as:

  • Rapid prototyping and modeling
  • Screws, bolts, fasteners, and fittings
  • Pistons and rods
  • Precision instruments
  • Furniture
  • Electronics housings
  • Panels

In general, CNC milling is a practical choice for precision components at all production volumes.

Custom CNC Milling from Expert Manufacturers

We understand that each of our clients has diverse requirements in their projects. There’s no “one size fits all” when it comes to manufacturing for demanding industries, such as the defense, aerospace, medical, and military sectors. Therefore, our custom CNC milling services provide the flexibility and freedom necessary to accomplish their specific guidelines and specifications.

Some benefits of custom CNC milling for your bottom line:

  • Greater flexibility: As mentioned before, flexibility allows our clients to achieve products based on their specific ideas or drawings. Our engineers will refine your ideas and ensure they meet your industry’s guidelines while maintaining functionality.
  • Improved precision: Custom CNC milling aims to produce precision parts, requiring advanced machines and cutting-edge techniques. We guarantee a quality finish to your product, resulting in minimal rework or rejection rates.
  • Reduced lead times: Lead times are crucial in any manufacturing project. We’re familiar with the importance of delivering products on time and within budget. Our custom CNC milling services enable us to expedite production without sacrificing quality and consistency.

Noteworthy Use Cases of Our Custom CNC Milling Services

Numerous industries can benefit from our custom CNC milling services. It allows us to maximize our state-of-the-art equipment while guaranteeing project success. Some examples of industries that can benefit from our services include:

  • Aerospace: Aerospace components must comply with rigorous regulations, ensuring all materials used in aerospace manufacturing are uniform. Our custom CNC milling can achieve precise outcomes that meet industrial standards. Some examples of aerospace products include satellite parts and flight control components.
  • Automotive: Exact specifications are a requirement for vehicle production to ensure the safety of its users and passengers. In addition, it can improve the vehicle’s performance, such as its fuel efficiency. Our custom CNC milling services can produce precise automotive components, such as engine blocks and transmission housings.
  • Construction: Harsh and demanding, the environments present in construction need durable and reliable components. Our advanced CNC milling techniques can produce robust parts that can withstand the wear and tear of construction works, such as heavy-duty bolts and connectors. These are used to manufacture off-highway and heavy-duty construction equipment and vehicles, such as bulldozers and cranes.

CNC Lathe

Lathing is a common application of CNC technology. CNC lathes move cutting tools back and forth across a rotating workpiece clamped in place. As with CNC milling, different numbers and types of cutting tools may be used, and the lathing stations may feature different axes of motion.

CNC lathing is the best choice for creating precision components with radial symmetry. Working from bar stock, CNC lathes allow manufacturers to produce shafts, barrels, fasteners, and other elements with defined outer and inner diameters.


In addition to CNC milling, our machining services include conventional milling, another subtractive manufacturing technique used to create custom metal components.

Conventional milling uses a rotary tool with an upward cutting pattern to chip metal off a workpiece. The cutting tool rotates in the opposite direction of the feed and removes the narrow end of the chip first, progressing upward toward the widest part of the chip. This method eliminates the backlash between the machine’s table and its lead screw.

Although CNC milling is ideal for complex components or high volumes, manual, conventional milling can be the faster and more affordable option for simple components at low production volumes. Conventional milling also allows our skilled technicians to manually add features when necessary.


One of the primary advantages of CNC milling and machining is that it can be applied to workpieces of all shapes and sizes. Whether working from a tiny blank or a large block of material, CNC machining services ensure consistent results with tight tolerances.

At Sinclair & Sons, we create large and small components from blocks and round bar stock, depending on our client’s needs, through custom CNC milling and machining. Our team can answer questions about specific dimensions, tolerances, and regulatory compliance.