Riveting is a method of permanently joining two or more pieces of metal using a small fastener called a rivet. The rivet passes through pre-drilled holes in the metal pieces, and then one end is deformed (squeezed or hammered flat) so it clamps the pieces tightly together. It’s one of the oldest joining techniques in metalwork, dating back to the Bronze Age, and it remains essential in aerospace, shipbuilding, and structural fabrication today.
How a Rivet Works
A rivet is a smooth, unthreaded metal pin with a pre-formed head on one end. To install it, you slide the shank through aligned holes in the pieces you want to join. Then the opposite end of the shank is deformed, either by hammering, squeezing, or pulling, until it mushrooms out and locks against the material. That deformed end is called the “shop head” or “buck-tail,” and together with the original head, it sandwiches the metal sheets in place.
Unlike a bolt, a rivet has no threads and can’t be unscrewed. That’s what makes it a permanent fastener. The joint holds through the physical clamping force of the two heads pressing against the material from both sides.
Types of Rivets
Different jobs call for different rivet designs. The most common types you’ll encounter in metalwork are solid rivets and blind rivets, though several others exist for specialized applications.
Solid Rivets
Solid rivets are the simplest and strongest type. They’re just a solid metal shaft with a rounded head. Installation requires access to both sides of the workpiece. You place the rivet through the hole, hold a heavy metal block called a bucking bar against the back, and strike the head with a hammer or pneumatic rivet gun. The tail end collapses against the bucking bar until it flattens and locks the joint. This often takes two people: one to hammer and one to hold the bucking bar in place.
Blind (Pop) Rivets
Blind rivets solve a common problem: what do you do when you can only reach one side of the material? These rivets have two parts, a hollow tubular body and a thin pin called a mandrel that runs through the center. You insert the rivet through the holes, then use a rivet gun to pull the mandrel backward. As the mandrel’s ball-shaped head gets pulled into the rivet body, it forces the back end to bulge outward, clamping the pieces together. Once set, the mandrel snaps off at a designed break point, leaving a secure joint. Blind rivets are standard in aircraft manufacturing, boat building, and any situation where the back side of a panel is inaccessible.
Other Types
- Semi-tubular rivets have a partially hollow shank that requires less force to set, making them useful for lighter-duty applications like electronics enclosures and leather goods.
- Drive rivets are a type of blind rivet with a short mandrel that you tap in with a hammer rather than pulling with a tool. They’re quick to install for non-structural work.
Rivet Head Styles
Rivets come with different head shapes depending on whether the surface needs to be smooth or whether maximum holding strength matters more. Universal heads are the most common general-purpose style, with a low, rounded dome that works in most applications. Countersunk heads sit flush with the surface of the material, which is critical in aerospace work where a protruding rivet head would create aerodynamic drag. Countersunk heads typically have an angle of 82° or 100°. Fillister heads have a taller, more prominent dome that provides extra bearing area for heavy-duty joints.
Choosing the Right Rivet Size
A standard rule of thumb is that the rivet diameter should be at least three times the thickness of the thickest sheet being joined. So if you’re riveting two sheets of 0.050-inch metal together, you’d calculate 3 × 0.050 = 0.150 inches and round up to the nearest standard size, which would be a 5/32-inch (0.156-inch) rivet. Going too small risks a weak joint; going too large means drilling unnecessarily big holes that weaken the surrounding material.
The rivet’s material matters too. Steel rivets are common for structural work, while aluminum rivets are standard in aerospace because they’re lighter and compatible with aluminum airframes. Copper rivets see use in roofing and decorative work.
Why Riveting Still Matters
Welding and bolting are more common in many modern applications, but riveting has specific advantages that keep it irreplaceable in certain industries.
In aerospace, riveting is preferred over welding because the heat from welding degrades aluminum alloys. Heat-treated aluminum gets its strength from a carefully controlled aging process, and welding temperatures destroy that strengthening effect. Riveting joins the metal cold, preserving the material’s full strength. Riveted joints also perform exceptionally well under repeated stress cycles, the kind of alternating loads an aircraft fuselage experiences thousands of times during pressurization and depressurization. The rivets distribute loads across many small connection points rather than concentrating stress along a weld line, which extends the structure’s fatigue life.
Riveting also handles mixed materials well. Modern aircraft and vehicles increasingly combine aluminum, titanium, and composite panels. You can’t weld aluminum to a carbon fiber composite, but you can rivet them together. This flexibility makes riveting essential for lightweight, multi-material designs.
Riveting vs. Welding vs. Bolting
Bolts have largely replaced rivets in structural steel construction because they’re cheaper to install and far easier to maintain. If a bolted joint needs repair, you simply unscrew the bolt. Replacing a rivet means drilling it out and setting a new one. However, bolts have a notable weakness: they can loosen under vibration, gradually losing clamping force over time. Rivets don’t have this problem because the deformed head physically cannot back out.
Welding creates the strongest possible joint by fusing the metal pieces into one continuous structure, but it comes with trade-offs. Welds shrink as they cool, which can distort the surrounding metal and must be accounted for in the design. Inspecting welds for hidden defects is also more difficult and expensive than inspecting riveted or bolted joints. And as mentioned, welding’s heat can damage heat-sensitive alloys and is incompatible with many non-metal materials.
Avoiding Corrosion in Riveted Joints
When a rivet and the surrounding metal are made of different metals, galvanic corrosion becomes a concern. This happens when two dissimilar metals are in contact and exposed to moisture: one metal corrodes faster than it normally would, essentially sacrificing itself to protect the other. The greater the difference in electrical potential between the two metals, the worse the corrosion.
The most effective prevention strategies include choosing rivet materials that are close in electrical potential to the base metal (aluminum rivets for aluminum sheets, for example), placing an insulating barrier between the metals using neoprene washers or plastic spacers, and sealing the joint with corrosion-inhibiting paste or paint to keep moisture out. A good general guideline is to maintain an anode-to-cathode surface area ratio of at least 10:1, meaning the more corrosion-prone metal should have the larger exposed surface area. In practice, this means you should avoid using small rivets of a reactive metal to fasten large panels of a more noble metal.
Tools for Riveting
For solid rivets, the basic toolkit is a hammer, a bucking bar, and a drill for making pilot holes. The bucking bar is just a shaped block of hardened steel that you hold against the rivet’s tail to give it something to deform against. In production settings, pneumatic rivet guns and rivet squeezers replace the hammer, driving rivets faster and more consistently using compressed air.
For blind rivets, you need a rivet gun designed to grip and pull the mandrel. Manual versions work like pliers: you squeeze the handles repeatedly until the mandrel snaps. Pneumatic models do this with a single trigger pull, which makes a significant difference when you’re setting hundreds of rivets in a shift. The choice between manual and pneumatic comes down to volume. For occasional repairs or small projects, a hand riveter is inexpensive and perfectly adequate. For production work, pneumatic tools pay for themselves quickly in time savings and reduced hand fatigue.