![\"5-axis-machined-part\"](\"https:\/\/chiggofactory.com\/wp-content\/uploads\/2025\/06\/5-axis-machined-part.png\")
<\/figure>\n\n\n\nMachined parts and components are precision objects created by removing excess material from a solid block, or \u201cworkpiece\u201d. Cutting machines\u2014 such as lathes, mills, drills, and routers\u2014 shape the workpiece to the desired form and finish. These parts can be made from metals, plastics, or other materials that maintain dimensional stability during cutting.<\/p>\n\n\n\n
Machining can be performed in two main ways:<\/p>\n\n\n\n
- \n
- Manual Machining:<\/strong> Operated by a skilled machinist who controls the tool movement directly, often using handwheels or levers.<\/li>\n\n\n\n
- CNC Machining:<\/strong> Fully automated using pre-programmed digital instructions, allowing for complex geometries, repeatability, and high efficiency\u2014particularly for custom or high-precision parts.<\/li>\n<\/ul>\n\n\n\n
Most complex or custom components are made on CNC machines for maximum precision and scalability. Nonetheless, manual machining still has its place\u2014especially for quick, one\u001eoff parts where setting up a CNC program would take longer than simply cutting by hand.<\/p>\n\n\n\n
In some cases, machining is used as a secondary or finishing process. For example, a part might be initially cast, forged, or injection-molded, and then undergo additional machining to refine its features\u2014such as drilled holes, tapped threads, or milled surfaces. These are often referred to as partially machined or post-machined parts.<\/p>\n\n\n\n
Common Machining Techniques and Processes<\/h2>\n\n\n\n
![\"Aluminum-High-Speed-](\"https:\/\/chiggofactory.com\/wp-content\/uploads\/2024\/12\/Aluminum-High-Speed-CNC-Turning.jpg\")
<\/figure>\n\n\n\nFrom simple holes to complex internal geometries, different machining techniques shape the key characteristics of machined parts. Below are some of the most widely used machining methods:<\/p>\n\n\n\n
- \n
- Milling:<\/strong> Uses rotating multi-point cutting tools to remove material from a workpiece along multiple axes. This process is highly versatile for creating complex surfaces, pockets, slots, and contoured shapes with high accuracy. The common types of milling operations include face milling, end milling, and slot milling.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Turning<\/a>:<\/strong> The workpiece spins against a relatively stationary cutting tool to generate cylindrical features\u2014shafts, rods, and bushings\u2014with tight dimensional control and smooth finishes.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Drilling: <\/strong>A rotating drill bit creates holes of various sizes and depths. It is one of the most fundamental machining processes, widely used for through-holes, blind holes, and threaded holes in mechanical parts.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Broaching: <\/strong>A toothed broach, with progressively larger teeth, cuts material in a single pass. It is particularly useful for cutting internal features like keyways, splines, and non\u001eround holes.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Grinding:<\/strong> A rotating abrasive wheel refines surface geometry and finishes to very tight tolerances. This technique is often used as a final finishing step for high-precision parts.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Electrical Discharge Machining (EDM):<\/strong> Electrical sparks in a dielectric fluid erode conductive workpiece material, enabling the creation of intricate shapes, sharp corners, and deep cavities in hard or delicate metals.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Laser Cutting: <\/strong>Uses a focused laser beam to melt, vaporize, or burn material, enabling precise and contact-free cutting. It is suitable for metals, plastics, and other materials, particularly in thin sheet form.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Ultrasonic Machining:<\/strong> Ultrasonic vibrations transmit an abrasive slurry against the workpiece, removing material from brittle or heat\u001esensitive materials (e.g., ceramics, glass) without thermal damage or mechanical stresses.<\/li>\n<\/ul>\n\n\n\n
What Are the Advantages of Machined Parts?<\/h2>\n\n\n\n
![\"CNC-Milling\"](\"https:\/\/chiggofactory.com\/wp-content\/uploads\/2024\/11\/CNC-Milling-1.jpg\")
<\/figure>\n\n\n\nCNC machined parts offer several key advantages over 3D printed and injection molded components. These benefits include:<\/p>\n\n\n\n
No Minimum Order Quantity (MOQ)<\/h3>\n\n\n\n
One of the main advantages of machined parts is that you don\u2019t need a minimum order quantity to purchase them. You can order a single prototype or very small quantities on demand\u2014 without the costly, time\u001econsuming tooling required for molded parts. This is especially useful for smaller companies, as it reduces inventory and capital tie\u001eup and supports customized production.<\/p>\n\n\n\n
Good Prototypes<\/h3>\n\n\n\n
Machined parts are suitable and affordable as prototypes because they avoid expensive tooling and minimum\u001eorder requirements. Programming and setup typically take only a few days, so teams can rapidly iterate designs and evaluate each version\u2019s fit and function in real\u001eworld tests. The high precision and superior surface finish of CNC machining ensure prototypes closely resemble final production parts, even for complex geometries or intricate details.<\/p>\n\n\n\n
Moreover, machining supports a wide range of materials\u2014from aluminum and steel alloys to engineering plastics<\/a>\u2014 developers can test multiple options under actual operating conditions and identify the optimal substrate before committing to large\u001escale manufacturing.<\/p>\n\n\n\n
Design Freedom<\/h3>\n\n\n\n
Machining offers unmatched design freedom by using multi-axis cutting tools to produce nearly any shape\u2014 deep pockets, undercuts, sharp corners, and intricate contours. You can integrate features such as threads, bosses, and keyways in a single setup, rather than designing separate inserts or adding them later.<\/p>\n\n\n\n
Injection molding, by contrast, demands design concessions\u2014uniform wall thicknesses, draft angles, and consistent flow paths\u2014to ensure proper mold filling and part ejection. Once the mold is built, modifying that design usually requires expensive tool changes or even a complete mold rebuild.<\/p>\n\n\n\n
Even\u00a03D printing process, generally seen as one of the best manufacturing processes<\/a> in terms of design freedom, has limitations. Most additive methods (especially FDM and SLA) cannot build steep overhangs without support structures. Those supports add material, increase print time, and must be removed post-print\u2014often leaving marks that need sanding or other finishing. Large or intricate parts may warp as layers cool, and the layer-by-layer build leads to anisotropic strength and visible \u201cstepping\u201d on vertical surfaces.<\/p>\n\n\n\n
Strength<\/h3>\n\n\n\n
Machined parts are cut from solid billets, which retain the full strength and material integrity of the stock. This makes them structurally superior to 3D printed parts, which can suffer from interlayer weaknesses, and to molded parts, which may require thinner walls for flow considerations.<\/p>\n\n\n\n
Faster Lead Times<\/h3>\n\n\n\n
Machined parts are produced much faster because there\u2019s no mold or special tooling to build. Once your CAD model is ready, a CAM program can be generated and sent directly to the machine. Modern CNC centers can operate around the clock with minimal supervision, allowing parts to be fabricated in just a few days. This speed is especially beneficial for rapid prototyping, bridge production, and urgent replacement needs.<\/p>\n\n\n\n
Surface Finish<\/h3>\n\n\n\n
Machined parts can achieve smooth, high-quality surface finishes without the flow lines, flash, or parting lines often seen in molded parts\u2014or the layer lines from 3D printing. By combining high spindle speeds, optimized feed rates, and proper coolant, machining can routinely achieve roughness values (Ra) <\/a>below 0.8\u202f\u00b5m\u2014and with fine finishing passes, even down to 0.2\u202f\u00b5m or better.<\/p>\n\n\n\n
Quality<\/h3>\n\n\n\n
CNC machines can hold tight tolerances and deliver consistent results from part to part. If a given feature\u2014such as a precision bore that must seal perfectly\u2014requires special attention, the machinist can spend extra time or make additional finishing passes on that feature without affecting the rest of the part.<\/p>\n\n\n\n
By contrast, injection\u001emolded parts depend entirely on the mold cavity\u2019s initial accuracy. After thousands of cycles, tool wear and slight process shifts can round off edges or change dimensions, and you can\u2019t tweak individual pieces without costly mold adjustments or secondary operations.<\/p>\n\n\n\n
Easy Alterations<\/h3>\n\n\n\n
Because CNC parts are produced directly from digital CAD files, you can make design changes right up until fabrication starts. This is invaluable during R&D and prototyping: engineers can fine-tune dimensions or test multiple versions without extra cost or wasted material.<\/p>\n\n\n\n
How to Design Machined Parts?<\/h2>\n\n\n\n
![\"Design](\"https:\/\/chiggofactory.com\/wp-content\/uploads\/2025\/06\/Design-Machined-Parts-1024x536.jpg\")
<\/figure>\n\n\n\nWhen designing machined parts, it is generally advisable to follow design for manufacturing (DFM) principles to ensure functionality, accuracy, and cost-efficiency. Fortunately, machined parts are not particularly difficult to design when you follow key machining design considerations<\/a> below:<\/p>\n\n\n\n
Wall Thickness<\/h3>\n\n\n\n
Thin walls are prone to deflection and vibration during machining, which can lead to dimensional inaccuracies and poor surface finish. As a general guideline, wall thickness should be no less than 0.8 mm for metal parts and 1.5 mm for plastic parts.<\/p>\n\n\n\n
Undercuts<\/h3>\n\n\n\n
Undercuts are recessed features that cannot be reached with standard cutting tools due to obstructing geometry. They require specialized tools, such as T-slot or L-shaped cutters, as well as additional machine setups and tool changes. For this reason, undercuts should only be used when necessary to the function of the part\u2014for example, when a locking groove, keyway, or assembly feature cannot be achieved by any other means.<\/p>\n\n\n\n
When designing undercuts in machining, it's best to make their dimensions in whole millimeters to match standard tool sizes. Undercut widths typically range from 3 to 40 mm, with depths up to twice the width.<\/p>\n\n\n\n
Protrusions<\/h3>\n\n\n\n
Tall, narrow protruding features\u2014such as bosses or posts\u2014are difficult to machine accurately and may cause tool chatter, vibration, or part distortion. To maintain stability and accuracy, the height of a protrusion should not exceed four times its width. Additionally, adding ribs or fillets can effectively reinforce protruding features and reduce stress concentration, making them more stable during the machining process.<\/p>\n\n\n\n
Cavities, Holes, and Threads<\/h3>\n\n\n\n
Cavities and pockets should be no deeper than four times their width to ensure proper chip evacuation and prevent tool deflection. Because end mills have a circular profile, internal corners always have a radius\u2014so avoid specifying perfectly sharp inside edges.<\/p>\n\n\n\n
Holes are typically made with drill bits or end mills. Since drill bits come in standard sizes, match hole diameters to standard tooling whenever possible. Also, limit hole depth to four times the diameter to maintain tool stability and drilling accuracy.<\/p>\n\n\n\n
Threads can be machined down to small sizes (e.g., M6 and below), but must balance strength and efficiency. As a guideline, use an engagement length of at least 1.5\u202f\u00d7\u202fnominal diameter (up to a practical maximum of 3\u202f\u00d7\u202fdiameter). Beyond that, extra threads add machining time and tool wear without significant load\u001ecarrying benefit.<\/p>\n\n\n\n
Scale<\/h3>\n\n\n\n
The size of a part must fit the capabilities of the machining equipment. For most milling operations, typical part dimensions should not exceed 400 \u00d7 250 \u00d7 150 mm. Larger parts may require advanced vertical or horizontal machining centers. Certain 5-axis milling machines can handle components up to 1000 \u00d7 1000 mm or even larger. For standard turning processes, the maximum workable size is about \u00d8 500 mm \u00d7 1000 mm.<\/p>\n\n\n\n
Minimum part size is generally limited by tool diameter and machine precision. For instance, if a feature is smaller than the tool itself, it cannot be machined. On standard machines, the minimum feature size typically ranges from 0.5 mm to 1 mm. For extremely small parts, micro-machining equipment or ultra-precision processes may be required to achieve the desired geometry.<\/p>\n\n\n\n
Machined Part Materials<\/h2>\n\n\n\n
![\"CNC](\"https:\/\/chiggofactory.com\/wp-content\/uploads\/2025\/06\/CNC-machined-parts-of-various-materials.jpg\")
<\/figure>\n\n\n\nMachined parts can be made from a wide variety of materials . The CNC machining material you select influences both mechanical properties\u2014such as strength, weight, and corrosion resistance\u2014and machining characteristics like cutting speed, tool wear, and surface finish. Softer materials are easier to cut but may deform; harder materials demand slower feeds and specialized tooling.<\/p>\n\n\n\n
Below are some materials commonly used for machined parts:<\/p>\n\n\n\n
- \n
- Metals: <\/strong>Aluminum<\/a>, Steel<\/a>, Stainless Steel<\/a> (17-4, Inconel 625 & 718), Titanium, Copper<\/a>, Brass<\/a>, Bronze, Zinc, Magnesium.<\/li>\n\n\n\n
- Plastics:<\/strong> ABS<\/a>, PC, ABS+PC, PP, PS, POM, PMMA (Acrylic), PAGF30, PCGF30, Teflon, DHPE, HDPE, PPS, PEEK, PA GF50, PPS GF50.<\/li>\n\n\n\n
- Composite Materials: <\/strong>Epoxy resin, Reinforced with carbon fiber, Fiberglass, Kevlar<\/li>\n\n\n\n
- Ceramics:<\/strong> Alumina, Zirconia, Silicon carbide, Boron nitride<\/li>\n<\/ul>\n\n\n\n
Machined Part Surface Finishes<\/h2>\n\n\n\n
![\"Powder](\"https:\/\/chiggofactory.com\/wp-content\/uploads\/2025\/06\/Aluminum-CNC-Machined-Parts-Powder-Coating-Process.jpg\")
<\/figure>\n\n\n\nA variety of post-processing options can be applied to machined parts to improve surface texture, appearance, and performance. Below are common surface finishes for CNC-machined parts:<\/p>\n\n\n\n
- \n
- As-Machined:<\/strong> No additional surface treatment. It reflects the natural surface condition of the part as it comes directly off the machine. Slight tool marks and surface variations may be visible. It is suitable for internal, non-cosmetic, or purely functional parts.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Bead Blasted: <\/strong>Abrasive media is blasted at the surface to create a uniform, matte texture. It helps remove burrs, sharp edges, and machining marks. However, it\u2019s important to note that the blasting process removes a small amount of material from the part, which may affect tight tolerances and delicate features.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Anodized:<\/strong> An electrochemical process commonly used on aluminum parts to improve corrosion and wear resistance. Type II anodizing creates a decorative and corrosion-resistant coating available in various colors. Type III anodizing (hard anodizing) produces a thicker, denser layer, offering greater abrasion and chemical resistance.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Powder Coated: <\/strong>Dry powder is sprayed onto the surface of the part, which is then heat-cured in an oven to form a hard, colored coating. This finish offers a strong, wear-resistant, and corrosion-resistant layer that is more durable than standard paint coatings.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n\n\n\n
- \n
- Polished:<\/strong> A mechanical process that uses fine abrasives or buffing wheels to achieve a smooth, reflective surface. Polishing improves aesthetics and can reduce surface roughness for components requiring low friction or visual appeal.<\/li>\n<\/ul>\n\n\n\n
Machined Part Tolerances<\/h2>\n\n\n\n
Machining tolerances are the permissible range of dimensional deviation, showing how much a finished part may differ from its nominal design dimensions. The tighter the tolerance, the higher the machining precision\u2014and the greater the manufacturing difficulty and cost. Components requiring precise fits or critical functions demand tight tolerances, while noncritical parts can be made to looser, more cost\u001eeffective tolerances.<\/p>\n\n\n\n
There are several international standards for machining tolerances, with ISO 2768 being one of the most widely adopted. This standard provides general metric tolerances (in millimeters) for linear and angular dimensions without requiring individual tolerance specifications. It classifies tolerances into four grades and helps manufacturers reduce ambiguity, maintain consistency, and optimize production costs. See the tables below:<\/p>\n\n\n\n
- Polished:<\/strong> A mechanical process that uses fine abrasives or buffing wheels to achieve a smooth, reflective surface. Polishing improves aesthetics and can reduce surface roughness for components requiring low friction or visual appeal.<\/li>\n<\/ul>\n\n\n\n
- Powder Coated: <\/strong>Dry powder is sprayed onto the surface of the part, which is then heat-cured in an oven to form a hard, colored coating. This finish offers a strong, wear-resistant, and corrosion-resistant layer that is more durable than standard paint coatings.<\/li>\n<\/ul>\n\n\n\n
- Anodized:<\/strong> An electrochemical process commonly used on aluminum parts to improve corrosion and wear resistance. Type II anodizing creates a decorative and corrosion-resistant coating available in various colors. Type III anodizing (hard anodizing) produces a thicker, denser layer, offering greater abrasion and chemical resistance.<\/li>\n<\/ul>\n\n\n\n
- Bead Blasted: <\/strong>Abrasive media is blasted at the surface to create a uniform, matte texture. It helps remove burrs, sharp edges, and machining marks. However, it\u2019s important to note that the blasting process removes a small amount of material from the part, which may affect tight tolerances and delicate features.<\/li>\n<\/ul>\n\n\n\n
- Plastics:<\/strong> ABS<\/a>, PC, ABS+PC, PP, PS, POM, PMMA (Acrylic), PAGF30, PCGF30, Teflon, DHPE, HDPE, PPS, PEEK, PA GF50, PPS GF50.<\/li>\n\n\n\n
- Metals: <\/strong>Aluminum<\/a>, Steel<\/a>, Stainless Steel<\/a> (17-4, Inconel 625 & 718), Titanium, Copper<\/a>, Brass<\/a>, Bronze, Zinc, Magnesium.<\/li>\n\n\n\n
- Ultrasonic Machining:<\/strong> Ultrasonic vibrations transmit an abrasive slurry against the workpiece, removing material from brittle or heat\u001esensitive materials (e.g., ceramics, glass) without thermal damage or mechanical stresses.<\/li>\n<\/ul>\n\n\n\n
- Laser Cutting: <\/strong>Uses a focused laser beam to melt, vaporize, or burn material, enabling precise and contact-free cutting. It is suitable for metals, plastics, and other materials, particularly in thin sheet form.<\/li>\n<\/ul>\n\n\n\n
- Electrical Discharge Machining (EDM):<\/strong> Electrical sparks in a dielectric fluid erode conductive workpiece material, enabling the creation of intricate shapes, sharp corners, and deep cavities in hard or delicate metals.<\/li>\n<\/ul>\n\n\n\n
- Grinding:<\/strong> A rotating abrasive wheel refines surface geometry and finishes to very tight tolerances. This technique is often used as a final finishing step for high-precision parts.<\/li>\n<\/ul>\n\n\n\n
- Broaching: <\/strong>A toothed broach, with progressively larger teeth, cuts material in a single pass. It is particularly useful for cutting internal features like keyways, splines, and non\u001eround holes.<\/li>\n<\/ul>\n\n\n\n
- Drilling: <\/strong>A rotating drill bit creates holes of various sizes and depths. It is one of the most fundamental machining processes, widely used for through-holes, blind holes, and threaded holes in mechanical parts.<\/li>\n<\/ul>\n\n\n\n
- Turning<\/a>:<\/strong> The workpiece spins against a relatively stationary cutting tool to generate cylindrical features\u2014shafts, rods, and bushings\u2014with tight dimensional control and smooth finishes.<\/li>\n<\/ul>\n\n\n\n
- CNC Machining:<\/strong> Fully automated using pre-programmed digital instructions, allowing for complex geometries, repeatability, and high efficiency\u2014particularly for custom or high-precision parts.<\/li>\n<\/ul>\n\n\n\n
![\"CNC-Machining-for-Automotive-Parts\"](\"https:\/\/chiggofactory.com\/wp-content\/uploads\/2025\/06\/CNC-Machining-for-Automotive-Parts.webp\")
<\/figure>\n\n\n\n![\"CNC](\"https:\/\/chiggofactory.com\/wp-content\/uploads\/2025\/06\/CNC-machining-service-at-Chiggo-1-1024x428.png\")
<\/a><\/figure>\n\n\n\n