Rivets: An Essential Fastener for CNC Machined Parts(tools for a lathe Martina)

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Rivets are one of the most common and versatile mechanical fasteners used in manufacturing and fabrication. A rivet is a short cylindrical rod with a head on one end that is inserted through holes in multiple layers of material. The tail end is then deformed with a rivet gun or other tool, causing it to expand and grip the inner surface of the hole. This creates a permanent mechanical attachment.
Rivets have been used for centuries in construction and industrial applications, but they remain extremely useful today, especially in computer numerically controlled (CNC) machining. Here are some of the top applications and benefits of using rivets in CNC machined parts and products:
Joining Thin Materials
One of the primary uses of rivets in CNC machining is to join thin sheets of metal and other materials. Rivets create solid fastening points without the need to thread holes or utilize nuts/bolts. This makes them ideal for fabricating enclosures, panels, housings, shields, and more from sheet metal. The riveting process concentrates force on a very small area, allowing thin materials to be securely fastened.
Rivets are commonly used with aluminum, steel, titanium, and composite sheets ranging from 0.5mm to 3mm thickness. Multiple rivets are spaced at regular intervals to distribute shear loads across the joint. Automated riveting systems can precisely control hole position and rivet installation to create consistent, robust connections.
Permanent Fasteners
Unlike screws, rivets form a permanent connection that cannot loosen over time. The deformed tail mechanically binds the rivet in place permanently. This makes rivets useful when assembling CNC machined components that require a one-time-only fastening.
Permanent fastening is important for products where vibration may cause threaded fasteners to loosen. It also eliminates any need to check or re-tighten fasteners. And because they do not unthread, rivets avoid the potential for loose objects inside critical systems and machinery.
Quick Installation
Compared to threading holes and adding nuts/bolts/screws, rivet installation is extremely quick and requires minimal tools. Operators can rapidly place rivets in pre-drilled holes and set them using manual, pneumatic, or hydraulic rivet guns. This simplicity means rivets are one of the fastest ways to join CNC machined parts on an assembly line.
For high production rates, automated riveting machines can install hundreds of rivets per minute. This keeps cycle times short and throughput high. The speed and ease of installation makes riveting a very scalable and efficient fastening method.
Improved Appearance
Unlike screws and bolts, properly set rivets have a clean, finished look. Their smooth, unthreaded exterior improves the aesthetic appearance of CNC machined products. Rivet heads can be countersunk to sit flush with the surface. And different rivet head styles allow further customization of the visible appearance.
Using rivets instead of exposed threaded fasteners provides a more streamlined look. This gives products a higher quality appearance, which may be preferred for consumer goods and high-end machinery. The smooth surface also eliminates places where dirt and debris can collect.
Lightweight Design
Rivets are extremely lightweight fasteners, especially compared to bolts and screws which require thick nuts and washers. Using rivets reduces part weight, which can improve performance in transportation equipment, aircraft, and other applications where reduced mass is critical.
The small footprint of rivets also decreases material requirements. More rivets can be arranged in less space versus other fasteners. High density riveting maximizes strength while minimizing weight.
Corrosion Resistance
Many rivet materials provide excellent corrosion resistance, including aluminum, stainless steel, and titanium. This makes rivets well-suited for machinery, structures, and enclosures exposed to weather and moisture. The riveting process also avoids bare threads that can initiate corrosion.
Proper material selection ensures riveted joints will maintain structural integrity in harsh operating environments. This is a key advantage over threaded fasteners that can rust and seize up over time. Using rivets improves long-term durability.
High Shear Strength
Riveting concentrates force into a very small footprint, resulting in fasteners capable of carrying high shear loads. The compressive force during installation deforms the rivet, cold working it to become stronger. This allows relatively small rivets to handle significant shear stress across joint lines.
High-strength structural rivets are used in critical mechanical joints for aircraft, bridges, pressure vessels, and other demanding applications. Aerospace-grade rivets made from exotic alloys can handle shear loads above 100,000 PSI. Proper rivet sizing and spacing distributes these loads efficiently across connections.
Low-Profile Attachment
The small diameter of most rivets allows them to attach components in tight spaces. Rivets can fasten overlapping sheets in very narrow gaps. This permits lower-profile and more compact CNC machined assemblies versus using protruding bolts/screws.
Low-clearance mounting also applies to equipment repairs and modifications. Rivets allow customized attachments and shims to be added when space is extremely limited. The minimal protrusion is valuable for retrofitting sensitive machinery.
Versatile Materials and Styles
Rivets suitable for nearly any application can be specified. Material choices include various aluminum, steel, stainless steel, copper, titanium, and nickel alloys. Rivets also come in standard, large-head, countersunk, round head, flat head, and specialized styles.
This breadth of options makes it easy to select optimum rivets based on strength, corrosion resistance, appearance, cost, accessibility, and other factors. CNC machined parts can use multiple rivet types to satisfy function, performance, and design goals.
Effective Blind Joining
Rivets are highly effective for blind joints where access is only available from one side. Bulbed and flush rivets expand on the inaccessible side, creating full-strength bonds without requiring part flip-over or fastener access on both sides.
Machined enclosures, covers, compartments, and structural members often utilize blind rivets. The riveting process applies force from outside to securely join the inner layers. This facilitates efficient, one-sided assembly of complex components.
Proven and Reliable
As one of the oldest mechanical fastening technologies, rivets are a proven and well-understood method. Extensive industrial experience has optimized rivet joint design across countless applications. Available specifications, extensive testing data, and time-proven service life provide confidence in riveted connections.
For critical CNC machined components like aircraft structures, rivets meet exacting quality standards that ensure consistent and reliable performance. As a trusted fastening solution, rivets are a low-risk design choice.
In summary, rivets provide a quick, lightweight, and reliable fastening method ideal for joining thin, high-strength, or corrosive environments in CNC machined products. Their versatility, shear strength, appearance, and ease of installation make rivets an essential fastener technology for innovative manufacturing. Whether used alone or in conjunction with other methods, rivets will continue improving fabricated parts and assemblies well into the future. CNC Milling