Everything You Need to Know About Machined Parts and Components: Definition, Advantages, Types, Design Guidelines, Applications

CNC machining

This comprehensive blog explores everything you need to know about machined parts and components. Discover their definition, advantages, types, design guidelines, and applications. Gain insights into machining processes, surface finishes, tolerances, and the importance of precision. Learn how to design machined parts effectively and explore real-world case studies. Whether you’re a designer, engineer, or industry professional, this blog provides valuable information for optimizing the use of machined parts in various industries.

Explore our CNC machining services and discover how we produce high-quality machined parts.

CNC machining

What are Machined Parts?

Machined parts are components created through the process of machining, a broad term referring to a controlled material-removal process. Machining involves a range of techniques, such as milling, turning, drilling, and grinding, to shape a piece of raw material into a desired form or part. This could involve transforming a metal block into a complex gear or a plastic rod into a precise instrument component.


The role of CNC machines in creating machined parts.

One of the primary tools used in the creation of machined parts is the CNC machine. CNC stands for Computer Numerical Control, a modern technology that uses computers to control machine tools. This method provides unprecedented precision, flexibility, and repeatability in part production, making it a cornerstone in machining parts.

There are various types of machined parts, each serving a unique purpose. Some common examples include gears, bushings, shafts, and housings, all of which are vital in mechanical systems. However, with advanced technology and skilled engineers, virtually any shape or form can be achieved through machining, from simple blocks to intricate 3D shapes.


Differences between machined, fabricated, and manufactured parts

The terms “fabricated” and “machined” are often used interchangeably, but they refer to distinct processes in the manufacturing industry. Fabrication generally involves processes like cutting, bending, and assembling parts, often used for creating large structures and components.

On the other hand, machining refers to detailed operations such as turning, milling, and drilling to create highly precise parts and components. While fabrication often creates the general shape or structure of a product, machining refines this shape to exact specifications.


Machined Metal: A Common Material

CNC machining

Machined parts can be made from a variety of materials, such as plastic, wood, and ceramics. However, metal is one of the most common materials used in machining due to its strength, durability, and versatility. Machined metal parts are used in everything from car engines to industrial machinery and even everyday household appliances.


Understanding “Easily Machined” Materials and Their Benefits

When a material is described as “easily machined,” it means that it is particularly suited to the machining process. These materials can be cut and shaped with relative ease, speed, and accuracy. They often generate less wear on the machining tools, resulting in cost savings for maintenance and tool replacement.

Easily machined materials usually have certain characteristics that make them ideal for machining. These characteristics might include good machinability (the material’s behavior under the cutting tool), a high melting point, and the ability to withstand the forces exerted during machining.


Commonly machined materials include:

Aluminum: Lightweight, strong, and highly machinable, aluminum is one of the most commonly machined materials. It’s used in a wide range of industries, from automotive and aerospace to electronics and consumer goods.

Brass: This alloy of copper and zinc is known for its excellent machinability and corrosion resistance. Brass is commonly used for components in electrical and plumbing applications.

Stainless Steel: While it’s more challenging to machine than aluminum or brass, stainless steel is prized for its strength and corrosion resistance. It’s commonly used for parts in the medical, aerospace, and food processing industries.

Plastics: Materials like acrylic, nylon, and Delrin are easily machined and offer unique advantages like low weight, electrical insulation, and resistance to corrosion.

Choosing the right material for your machined part is critical to its performance, longevity, and overall cost. You can learn more about this topic in our dedicated blog post “Choosing the Right Material for Your CNC Part”.

Why Need Machined Parts?

Machined parts play a vital role in countless applications across various industries. The precision and customizability provided by machining processes allow for the production of components with complex geometries and tight tolerances that would be challenging, if not impossible, to achieve through other manufacturing methods.


Importance and Benefits of Machined Parts in Various Industries

Aerospace: In this industry, precision is paramount. Machined parts are critical for the manufacture of aircraft components, with tight tolerances and high-quality materials ensuring safety and performance.

Electronics: From circuit boards to connectors, many electronic components are machined to ensure precise fit and function. These parts often need to withstand high temperatures and corrosive environments, making material selection and surface finish critical.

Automotive: Machined parts in this industry range from engine components to structural elements. The precision offered by machining ensures efficiency and safety.

CNC machining

Medical: Surgical instruments, implants, and medical devices often require custom machined parts. The use of bio-compatible materials and the ability to create complex geometries make machining ideal for this industry.


Machining versus manufacturing: Key distinctions and when to use each process.

While all machining is a type of manufacturing, not all manufacturing involves machining. Manufacturing is a broad term encompassing all processes used to turn raw materials into finished products. This includes methods like casting, molding, forging, and, of course, machining.

Machining, on the other hand, is a subset of manufacturing that involves the removal of material from a workpiece to create a desired shape or feature. It offers a high degree of precision and can produce complex parts that might be difficult or impossible to create through other methods.

If you need a detailed explanation about this, refer to our article, “What is CNC Machining?”


The role of machined parts in product efficiency and quality control.

Efficient and high-quality products often rely on precisely machined parts. Machining allows for tight tolerances, meaning parts fit together as they should with minimal variation. This precision reduces the likelihood of product failures and increases overall product lifespan.

Moreover, quality control is inherently built into the machining process. With advanced CNC machines, each part can be created to exact specifications, ensuring consistency across large production runs.

What are the Advantages of Machined Parts?

Machined parts offer several advantages over parts created using other manufacturing methods. The inherent precision of machining processes and the range of materials that can be used are just the starting point.


Precision and Consistency

The use of advanced CNC machining technology allows for highly precise parts. CNC machines follow digital plans to the letter, minimizing errors and ensuring that each part matches the design perfectly. Whether you’re making one part or a thousand, each will be almost identical, guaranteeing consistency across your entire production run. For a detailed understanding of this precision and consistency, refer to our article “What is the technical meaning of precision CNC machining?”


Versatility in Design and Material

CNC machining can handle virtually any design, no matter how complex. From intricate curves to tight corners, machining can create parts that would be difficult or impossible to manufacture otherwise. The range of materials available for machining is also expansive, from plastics and woods to metals and alloys.


Quick Production and Prototyping

CNC machines can produce parts quickly, making them ideal for both prototyping and mass production. Additionally, because the design process is digital, changes can be made quickly and without significant downtime. This speed and flexibility can drastically reduce the time it takes to bring a product to market.


Durable and Strong Parts

Machined parts are typically stronger and more durable than those produced by other methods. The machining process doesn’t introduce internal stresses in the way that casting or molding can, and the materials used in machining tend to be strong and resistant to wear.


No Minimum Order Quantity (MOQ)

One of the key advantages of machined parts is that there is no minimum order quantity. This flexibility allows you to order as per your exact needs, whether you require a single piece for prototyping or a large batch for full-scale production. This can be a major benefit for smaller businesses or startups, who may not require large quantities initially. In addition, the absence of MOQ makes it possible for us to cater to your unique needs without the risk of excess inventory.


Design Freedom

CNC machined parts offer unparalleled design freedom. Using advanced CNC machines, we can produce virtually any part design, regardless of its complexity or size. Whether you need parts with intricate features, complex geometries, or very fine details, CNC machining can handle it all. The design freedom afforded by CNC machining also makes it possible to make modifications or improvements to your part design quickly and efficiently.



When it comes to the quality of machined parts, CNC machining stands out. Thanks to the precise control offered by CNC machines, we can produce parts that meet the highest quality standards. With CNC machining, you can expect tight tolerances, fine finishes, and parts that match your design specifications perfectly. This level of quality is particularly important in industries such as aerospace, electronics, military, and medical, where precision is critical.


Lead Times

With CNC machining, lead times are significantly shorter compared to other manufacturing methods. We can produce a prototype within 3 working days, and we can support both small batch and mass production. Our speedy turnaround times can help you bring your product to market faster, giving you a competitive edge.



CNC machining allows for easy alterations to part designs. If you find that your part needs to be adjusted or changed, we can quickly update the machine programming and produce a new part that meets your revised specifications. This capacity for easy alterations helps to reduce development time and costs, as well as enhance the final product.

How to Design Machined Parts?

Designing machined parts effectively requires a balance of creativity, technical skill, and practical knowledge about the machining process. From the choice of materials and design considerations to the specifics of the machining process, several factors come into play.


Best Practices for Designing Machined Parts

To ensure optimal functionality and efficiency, here are some best practices for designing machined parts:


Inside Corner Radii

CNC machining

Inside corner radii refer to the curvature at the inside corners of a part. When designing machined parts, it’s important to avoid sharp corners, as they can pose challenges during the machining process. Sharp corners can result in tooling issues, such as excessive tool wear, increased machining time, and potential for part damage.
For machined parts made from softer materials like plastics, radii in the range of 0.5 mm to 2.0 mm (0.02 inches to 0.08 inches) are often suitable.

For machined parts made from metals, radii in the range of 1.0 mm to 3.0 mm (0.04 inches to 0.12 inches) are commonly used.

In some cases, larger radii may be required for parts subjected to higher loads or where additional strength is needed. These larger radii can range from 3.0 mm to 6.0 mm (0.12 inches to 0.24 inches) or more, depending on the specific application


CNC machining

Pockets refer to recessed areas within a part. When designing pockets for machining, consider the following guidelines:

Determine Pocket Depth: 2 to 4 times the cutting tool diameter are commonly used.
Wall Thickness:the wall thickness should be at least 1.5 to 2 times the diameter of the cutting tool being used.



Cavities are hollowed-out spaces within a part that serve various purposes, such as housing electronic components or creating complex internal structures.


Pre-Drill Tapping Depth

When designing parts that require threaded holes, it’s important to specify the pre-drill tapping depth. This is the depth to which the hole is pre-drilled before tapping threads into it. The pre-drill tapping depth ensures that the threaded portion of the hole has sufficient depth for proper thread engagement.

The pre-drill tapping depth should be determined based on the specific threading requirements, including the thread size and pitch. It’s essential to follow industry standards or consult with a machinist to ensure accurate and reliable thread engagement.


Tapped Holes

Tapped holes are threaded holes created in a part to allow for the insertion of screws or bolts. When designing parts with tapped holes, it’s essential to consider the following:

Thread Size and Pitch: Determine the appropriate thread size and pitch based on the specific application and fastener requirements. This information will help guide the design of the tapped hole.

Hole Diameter: The hole diameter should be designed to accommodate the thread diameter and allow for proper thread engagement. It’s important to consider the recommended hole sizes for different thread types, which can be found in engineering references or consulted with a machinist.

Thread Relief: Adding a thread relief at the bottom of the tapped hole can help ensure accurate thread formation and prevent binding. The thread relief provides clearance for the displaced material during tapping.



CNC machining

Undercuts refer to features in a part where the cross-section is narrower than the adjacent areas. These features are often used to create interlocking mechanisms, such as snap fits or retention features. When designing parts with undercuts, consider the following:

Draft Angles: Incorporate draft angles to facilitate the release of the part from the mold or machining tool. This helps prevent damage to the part and ensures smooth ejection during production.

Tool Access: Ensure that the machining tools can reach and properly machine the undercut areas. This may involve using specialized tools or employing multi-axis machining techniques to achieve the desired result


Wall Thickness

Proper wall thickness is crucial for the structural integrity and manufacturability of machined parts. Consider the following guidelines when determining the wall thickness of your design:

Material Properties: Different materials have varying requirements for minimum wall thickness. Research the specific material properties to ensure that the chosen thickness provides sufficient strength and functionality.

Uniformity: Maintain consistent wall thickness throughout the part to avoid stress concentration and potential warping during machining or use.

Support Structures: For parts with large or thin sections, consider incorporating support structures or ribbing to improve rigidity and minimize deflection during machining.


Text and Lettering

Including text or lettering on machined parts is common for identification, branding, or instructional purposes. To ensure legibility and successful machining, follow these guidelines:

Font Selection: Choose a font that is clear and readable, particularly when scaled down to the required size. Avoid overly complex or ornate fonts that may be challenging to machine accurately.

Character Size: Consider the size of the characters in relation to the part’s overall dimensions. Ensure that the characters are large enough to be machined accurately and legible when the part is in use.

Depth and Surface Treatment: Specify the desired depth of the text or lettering to achieve the desired visual effect. Depending on the material and application, consider incorporating surface treatments like engraving or etching to enhance visibility.


Surface Finish

Different machining processes yield different surface finishes. Knowing what kind of surface finish you need for your part is essential to the design process. For more on surface finish for your CNC machined parts, check out these 10 Tips for Better Surface Finish.


Understanding the roles of milling and machining in the design process.

Milling and machining are integral parts of the design process for machined parts. Milling is a specific type of machining process where a cutter removes material from the workpiece surface. In contrast, machining is a broader term that encompasses many different processes, including milling.

CNC machining

Machining influences the design process in a few key ways:

Part Geometry: The capabilities of the machine tool being used can constrain the geometry of the part. For example, the ability of a machine to perform complex 3D operations will determine whether certain part geometries are feasible.

Material Removal: The machining process can efficiently remove material in specific areas of the part to achieve the desired shape and size. This capacity for material removal shapes the design process.


The Contribution of Lathe Parts and Machinery Parts in Machined Part Design

The lathe is an essential tool in the machining process. Lathe parts like the chuck, carriage, and spindle all contribute to the effective design of machined parts. Their efficient operation ensures precision and quality in the final product. Machinery parts like the motor, control panel, and tool turret also play a vital role in machining. Their performance affects the efficiency and accuracy of the machining process.

Designing machined parts is a complex task that requires a deep understanding of the machining process, the capabilities of machine tools, and the material properties. Understanding these key aspects can greatly aid in designing efficient and functional machined parts. For more in-depth insights and professional advice on designing machined parts, we encourage you to explore our CNC machining services.

Types of Machined Parts

Machined parts come in all shapes and sizes, each with its unique purpose and advantages. Let’s explore some of the common types of machined parts:

Machined Metal Parts: These are parts that are machined from various types of metal such as steel, aluminum, brass, or copper. Each metal has its unique properties that make it suitable for certain applications. For instance, machined aluminum parts are lightweight, resistant to corrosion, and excellent for heat dissipation, making them ideal for use in automotive and aerospace applications.

Milled Parts: These are parts produced through the milling process, where a rotating cutting tool is used to remove material from a workpiece. Milled parts can be incredibly precise and can have complex geometries, making them suitable for a wide range of applications.

Lathe Parts: Parts produced on a lathe, often referred to as turned parts, are rotated against a cutting tool to remove material. This process is ideal for producing parts with a symmetrical shape about an axis, such as shafts and rods.

CNC Parts: CNC, or computer numerical control, parts are produced using a computer-controlled machine. This allows for high precision and complex geometries. The wide variety of CNC machined parts include gears, bushings, manifolds and more.

Custom Machined Parts: These are parts that are specially designed and machined to meet specific customer requirements. They can be made from a variety of materials and can have unique shapes and features.

Machined Part Surface Finishes

Machined parts can be given a variety of surface finishes to enhance their functionality, durability, and aesthetics. The surface finish of a part can have a significant impact on its performance and lifespan. So, what are the surface finish options for machined parts, and how do they affect a part’s properties?

Surface finishes in machined parts vary significantly depending on the application and material used. Some of the common options include:

As-Machined Finish: This is the standard finish you get right after the machining process. It might exhibit some tool marks but is generally acceptable for many applications.

Bead Blasting: This process uses glass beads blasted at the surface to provide a smooth and non-reflective finish.

Anodizing: Anodizing is a common finish for aluminum parts. It not only enhances wear and corrosion resistance but also provides better adhesion for paint primers and glues.

Powder Coating: This finish provides a hard, durable, and corrosion-resistant layer to the parts. It’s available in a variety of colors, making it suitable for parts that need aesthetic appeal.

Polishing: Polishing gives parts a shiny and smooth finish. It’s commonly used for aesthetic purposes or when a high degree of smoothness is required.

For a deeper understanding of types of metal finishes, you can visit this page.


Achieving Various Surface Finishes

Achieving a specific surface finish involves a series of processes. As-machined finish is the simplest as it requires no additional steps after machining. Other finishes, however, require post-machining processes.

For instance, bead blasting involves the use of a blasting machine where glass beads are shot at the part under high pressure. Anodizing, on the other hand, involves submerging the part in a chemical bath and applying an electrical current.

In the case of powder coating, the part is first cleaned and prepped before a dry powder is sprayed onto its surface. The part is then baked in an oven, causing the powder to form a hard, durable layer.

For a comprehensive understanding of how to achieve a better surface finish for your CNC machining parts, I suggest checking this insightful article.


Impact of Surface Finishes on Machined Parts

The surface finish of a part can significantly impact its functionality, durability, and aesthetics. A smooth surface finish, for instance, reduces friction, making the part operate more efficiently. Some surface finishes, such as anodizing and powder coating, enhance the corrosion and wear resistance of parts, increasing their durability. Additionally, surface finishes can significantly enhance the appearance of machined parts, which is crucial for parts used in visible applications.

Understanding the importance of surface finish in machined parts is crucial in the design and manufacturing process. By choosing the right surface finish, you can enhance the performance and lifespan of your machined parts.

Machined Part Tolerances

Tolerance in the realm of machining refers to the allowable amount of variation in the physical dimensions of a manufactured part. When you request a part of a certain size from a machine shop like Worthy Hardware, the final product won’t be exactly to that measurement – but it will be very close. This close-but-not-exact measurement is a consequence of the realities of material properties, tool wear, and myriad other factors affecting machining processes.


The Role of Precision and Tolerances in the Machining Process

Precision and tolerances are key factors in the machining process, significantly impacting the final product quality. In essence, the level of precision describes how closely all produced parts match each other in dimensions, while tolerance explains how much the parts can deviate from the intended design without negatively affecting their function or assembly.

For instance, in the production of CNC parts, maintaining high precision ensures each part is uniform, leading to consistency in assembly and product quality. Similarly, defining acceptable tolerances guarantees the machined parts will fit together and operate as expected, even if they aren’t exactly to the intended dimensions.


Achieving High Precision Tolerances

Achieving high precision tolerances is critical in industries like aerospace and medical, where the smallest deviation could lead to severe operational failure or risk lives. How do we achieve such tight tolerances?

Primarily, the equipment used plays a significant role. At Worthy Hardware, our precision CNC turned parts are produced using advanced CNC machines that offer high accuracy levels.

In addition, factors like temperature control and tool wear monitoring can impact the ability to maintain high precision tolerances. Techniques such as grinding, honing, and lapping can also be applied post-machining to enhance accuracy.

Last but not least, the experience and skill of the machinist are invaluable. Understanding how different materials react to various machining processes, the machinist’s skill in setting up and running the machine all contribute to achieving the desired tolerances.

With a deeper understanding of tolerances, one can appreciate the level of detail that goes into creating machined parts, particularly those demanding high precision. For more information on how we influence tolerance in CNC machining at Worthy Hardware, you can check out this article.

What are the Applications of Machined Parts?

Machined parts have become indispensable in our everyday life, playing critical roles in a broad range of industries and applications. From aerospace and automotive to electronics and medical devices, machined parts contribute to the function and reliability of countless products.


Aerospace and Automotive

In the aerospace industry, precision is paramount. The complex components found in aircraft engines, such as turbine blades, are often created using high-precision machining. Even the smallest discrepancy can lead to catastrophic failure, underscoring the importance of precision machined components in this industry.

Similarly, the automotive industry relies heavily on machined parts. Engine blocks, gears, pistons, and myriad other parts are all created through machining processes. Manufacturers are increasingly using advanced machining methods like 5-axis CNC machining for creating complex parts with high efficiency and precision.



Machined parts are equally prevalent in the electronics industry. From small parts machining required for tiny connectors and pins to larger components like heat sinks and cases, machined components ensure the functionality and reliability of electronic products. For example, precision CNC machining is often employed to create custom-made parts for bespoke electronic products, allowing for design freedom and flexibility.


Medical Devices

In the medical industry, machined parts are used in a wide array of applications. Surgical instruments, implants, and even complex diagnostic equipment are manufactured using precision machining. Given the importance of safety and accuracy in medical procedures, these parts often require high-precision tolerances, achievable through techniques like Swiss screw machining.

One case study worth mentioning is the production of orthopedic implants, where machined parts play a vital role. To successfully replace or support damaged body parts, implants must fit perfectly with the patient’s body, making precision critical. Machining, particularly CNC machining, is often used to create these implants, as it provides the required precision and allows for the creation of complex geometries.


Other Applications

Additionally, machined parts find their way into sectors like renewable energy, where parts for solar panels and wind turbines are often machined. In the field of robotics, machined components form the core of many robotic systems, while in the military, everything from vehicle parts to firearms components are created through machining.

In essence, machined parts are everywhere, contributing to the world’s progress in myriad ways. For more insights into the applications of numerical control machining in various fields, you can visit this page.

How to Outsource Machined Parts?

As the demand for machined parts grows, so does the need for outsourcing these components. Outsourcing can provide access to specialized machinery and expertise, often at a lower cost and with shorter lead times than maintaining an in-house machining operation. Here’s a guide on how to successfully outsource your machined parts:


Identify Your Requirements

The first step to outsourcing machined parts is to thoroughly understand your requirements. This includes the type of material you wish to use, the quantity of parts needed, the level of precision required, and your preferred lead time. For instance, if you require small parts machining, you will need to find a supplier that specializes in producing small-scale components. Similarly, if you need CNC machined products, you’ll want a supplier with advanced CNC capabilities.

Choose the Right Outsourcing Partner

Once you have defined your requirements, the next step is to find an outsourcing partner that can meet them. There are several key factors to consider when selecting a supplier. These include the supplier’s capacity, capabilities, quality assurance processes, and previous experience in your industry.

Look for a machinery parts manufacturer with a solid reputation for delivering high-quality products on time. They should also have strong quality control procedures in place and be able to demonstrate a proven track record of meeting client specifications.

A valuable tip is to consider their technical capabilities. Can they handle custom machined parts? Are they experienced with the material you want to use? Can they produce your parts within your desired timeframe? For instance, if you need lathe parts, ensure that the supplier has advanced lathe machines and experienced operators.


Develop a Strong Working Relationship

Building a strong relationship with your outsourcing partner is crucial. Effective communication is key to ensuring your expectations and requirements are clearly understood. Regularly review the supplier’s performance and provide feedback to help them meet your needs better. Remember, a strong partnership can lead to better quality machined parts and smoother overall operations.

It’s also vital to visit the supplier’s premises if possible. This allows you to see their operation firsthand and assess their capabilities more accurately. You can check their machinery, ask about their production process, and even meet the team responsible for creating your machined parts. This also demonstrates your commitment to quality and could help to further strengthen your partnership.

Outsourcing machined parts can be a complex process, but with careful planning and management, it can lead to significant benefits. For further tips on choosing the right contract manufacturer for your CNC machining parts, check out this guide.

Remember, the key to successful outsourcing is finding the right partner who understands your needs, has the capabilities to meet them, and values a strong client-supplier relationship. With this approach, you can ensure you get the high-quality machined parts you need while also optimizing your production costs and timelines.


In conclusion, understanding the intricacies of machined parts is essential for successful design and manufacturing. By following the design guidelines, considering material properties, and collaborating with experienced professionals, you can create high-quality machined parts tailored to your specific needs. Ready to bring your machined part project to life? Contact us today for expert assistance and a reliable partnership in delivering top-notch machined components.