Aluminum Dome Head Tri-Fold Rivets

What are aluminum dome head tri-fold rivets? These are tri-fold rivets with an all aluminum body and mandrel and a standard low profile dome head, supplied with a sealing washer. The body folds into three legs on the blind side for a wide clamping footprint, while the matched aluminum construction avoids any dissimilar metal in the joint. That combination makes them the natural choice for aluminum trailer, RV, and panel work where the rivet must hold in thin skin without corroding against it. AlbanyCountyFasteners.com stocks these in 3/16 and 1/4 inch.

Aluminum - Aluminum Mandrel

Rivet Number, Diameter:

Why aluminum tri-fold rivets for panel work?

Because thin aluminum skin creates two problems at once and this rivet solves both. The first is mechanical: aluminum panel is soft, and a conventional blind rivet forms a tight ring behind it that concentrates all the holding force on a small area, which dimples the skin or pulls straight through under wind load and road vibration. The folding legs spread that force wide enough to hold. The second is electrochemical: a steel or stainless rivet in an aluminum skin makes the aluminum the sacrificial metal, and in road spray or weather the holes gradually enlarge as the panel corrodes around each fastener. All aluminum construction removes the couple entirely.

Why choose aluminum dome head tri-fold rivets

Three folding legs prevent pull-through in thin aluminum skin
No dissimilar metal in the fastener, so no galvanic corrosion against aluminum
Sealing washer under the head for a weather resistant joint
Holds well in elongated and oversized holes from previous fasteners
Light and easy to set, so a standard riveter handles them comfortably

Sizes and grip ranges

3/16 inch in grip ranges from 0.250 through 0.500 inch
1/4 inch in grip ranges from 0.250 through 0.625 inch
Order by body diameter, then match grip range to your total material stack
Include the sealing washer thickness in the grip calculation

Common applications

Aluminum trailer skins, RV panels, and horse trailer bodies
Aluminum siding, cladding, and metal building panels
Thin gauge aluminum sheet in exterior service
Repairs over enlarged holes in aluminum panels
Boat trim, awnings, and marine panel work
Any aluminum joint exposed to weather or road spray

Where the head must match solid rivets, use aluminum shave head tri-fold rivets. On steel panels, steel dome head tri-fold rivets are the correct pairing.

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Aluminum Dome Head Tri-Fold Rivet FAQs

Will these hold in thin aluminum skin?

That is what they are built for. The three folded legs create a much larger bearing footprint than the compressed ring a standard rivet forms, so the holding force spreads across enough skin to resist pull-through under vibration and wind load.

Can I use these on a steel frame under aluminum skin?

Yes, and it is common. The rivet contacts the aluminum skin at the head, which is where galvanic corrosion would show. The legs bearing on a steel frame behind is a much lower risk than a steel head against aluminum skin.

How strong are they?

Tri-fold rivets are non-structural, chosen for clamp and holding power rather than shear capacity. Aluminum with an aluminum mandrel sits at the lower end of the strength range, which is the trade for galvanic compatibility.

Do they need a special tool?

No, any standard blind rivet tool sets them. The larger formation means a longer pull, so use a riveter with full stroke travel. Aluminum sets easily enough that a hand tool works across both sizes.

Is the sealing washer removable?

It can be removed if your application needs the head flat against the panel, though you lose the watertight seal. A urethane sealant in the hole and on the rivet body restores most of it if you go that route.

What if my hole has enlarged?

These handle elongated holes better than conventional rivets because of the wide leg footprint. If the hole is significantly oversized, step up to the 1/4 inch size or add a backing washer behind the panel.