Large Flange Rivets

When do I need a large flange rivet?

Three situations call for one. The first is soft material, where plastic, fiberglass, wood, or thin gauge sheet will not support a standard head and it crushes in or pulls straight through under load. The second is an oversized or damaged hole, which happens constantly in repair work when the original fastener has wallowed out its hole and you need something that covers rather than something that fits. The third is anywhere the joint sees a pull-out load rather than pure shear, since the head area is what resists a panel being pulled off the rivet. The tradeoff is appearance, because a large flange head is visible and sits proud of the surface.

Why choose large flange rivets

• Much larger bearing area resists pull-through in soft and thin material
• Covers oversized, elongated, or damaged holes in repair work
• Better performance under tensile and pull-out loading than a standard dome head
• Reduces the need for a separate backup washer on the head side
• Available in matched materials for corrosion critical outdoor work

Material options

• Aluminum with aluminum mandrel, lightweight with matched materials, good for aluminum panels and soft stock
• 304 stainless with stainless mandrel, highest strength and corrosion resistance for exterior and marine use
• Zinc plated steel with steel mandrel, strong and economical for general indoor and light exterior work

Common applications

• Fastening to plastic, fiberglass, composite, and wood panels
• Thin gauge sheet metal, where a standard head would pull through
• Repair work over oversized or elongated holes
• Trailer skins, truck bodies, and transportation panels
• Signage, awnings, and architectural cladding
• Roofing and siding panels subject to wind uplift

Where appearance matters more than bearing area, countersunk rivets sit flush instead. For very soft or brittle material, tri-fold rivets spread load on the blind side too, and rivet washers add support behind any style.

Related Categories

• Blind Rivets
• Open End Rivets
• Tri-Fold Rivets
• Countersunk Rivets
• Rivet Washers

Large Flange Rivet FAQs

How much bigger is a large flange head?

Substantially, usually around three times the body diameter compared with roughly twice for a standard dome head. That difference translates into far more bearing area, which is the whole point, since bearing area is what resists pull-through.

Do large flange rivets replace a backup washer?

On the head side, often yes. On the blind side, no. The flange spreads load where the head sits, but the formed body on the far side is unchanged. If the back material is soft, add a rivet washer behind the joint as well.

Can I use large flange rivets on oversized holes?

That is one of their main uses, within limits. The flange must fully cover the hole with margin all around, and the body still needs to be reasonably supported by the hole. If the hole is badly enlarged, step up to a larger rivet diameter rather than relying on the flange alone.

Will the head sit flush?

No, it sits proud of the surface by design. If you need a flush finish, use countersunk rivets in a countersunk hole. Large flange and flush are opposite solutions, one maximizing bearing area and the other minimizing profile.

Which material for outdoor panels?

304 stainless with a stainless mandrel for anything coastal, exposed, or long-life. Zinc plated steel works for general exterior use at lower cost but will eventually corrode at the mandrel break. Aluminum suits aluminum panels where galvanic matching matters more than absolute strength.

Do they need a different tool?

No, standard blind rivet tools set them. Make sure the tool nosepiece clears the larger head, which is rarely an issue but worth checking with compact or angled riveters.