Comparing blind rivets and solid rivets for repairs

Why the choice matters before you pick up a drill

Riveting is one of those jobs that looks simple until you get it wrong and end up with a joint that rattles, weeps water or fails at the worst possible moment. The two families you will meet most often are blind rivets — the pop rivets in the tin from the local hardware shop — and solid rivets, the traditional hammer-and-buck type that built everything from Spitfires to narrowboats.

Both make permanent joints in sheet metal. They are not interchangeable in strength terms, and choosing the wrong one is the most common mistake in DIY repair work. This guide sets out how each behaves, how they are installed, and which jobs suit which.

Blind rivets: one-sided access, quick and forgiving

A blind rivet is set by pulling a mandrel through the rivet body with a hand tool. The tail mushrooms out behind the workpiece and the mandrel snaps off at a designed load. You only ever need access to one side, which is exactly why they dominate repair work on vehicles, trailers, caravans and garden machinery.

Common sizes are 3.2mm, 4.0mm and 4.8mm body diameter, in aluminium, steel, stainless and monel. Closed-end or sealed types retain the mandrel head and resist water ingress far better than open types — worth the small extra cost on anything left outdoors.

• Set with a cheap hand tool, lazy tongs or an air-hydraulic gun; minimal skill required
• Ideal for box sections, enclosed panels and anywhere you cannot reach the back
• Tolerant of slightly oversized or misaligned holes
• Lower shear and tensile strength than a solid rivet of the same diameter
• Clamping force is limited, so gaps and buckled panels can survive under a rivet head
• Open types are not watertight, and the spent mandrel can rattle around inside a closed section

Solid rivets: the strongest joint you can hammer home

Solid rivets need access to both sides. One person holds a bucking bar against the tail while the other drives the head with a rivet gun or air hammer, or the whole job is squeezed together in a rivet squeezer. The tail deforms into a second head — the shop head — and the shank swells to fill the hole completely.

In aluminium work, 2117-T4 is the classic general-purpose alloy: soft enough to set with a 2x or 3x gun, strong enough for structural repairs. 2017-T4 is harder again, while monel, copper, mild steel and stainless rivets cover marine, workshop and historic applications.

Strength, hole fit and material differences

This is where the two types genuinely part company. A well-set solid rivet fills its hole, so load passes through the shank into the surrounding metal. A blind rivet only swells partially, and its strength is limited by the mandrel and the thickness of its own wall. As a rule of thumb, expect a solid rivet to be roughly three to four times stronger in shear than a blind rivet of the same diameter, and much more resistant to vibration loosening.

Hole preparation matters more with solid rivets. Drill to a snug fit — typically around 0.1mm clearance — deburr both faces, and never rely on an oversized hole. Blind rivets are more forgiving but you must match the grip range stamped on the packet to the total thickness of the material; too long and the tail will not form properly, too short and the rivet will not clamp.

Installation methods and tooling compared

Blind riveting needs a drill, a riveter and a few seconds per fastener. Solid riveting needs more kit: a rivet gun with a regulator, a set of bucking bars, rivet sets, and usually a second pair of hands. A squeezer is quieter and cleaner for straight runs of accessible rivets, but it will not fit everywhere.

Technique counts. Hold the bucking bar firmly against the tail with real pressure, use short bursts rather than long pulls, and keep the gun square to the work. If the rivet bends over instead of forming a neat dome, the hole is too big or the bar was not held tight enough. Practise on scrap sheet before touching anything visible.

Spacing follows the same rules for both types: keep rivets roughly three to four diameters apart and at least two diameters from any edge, and use countersunk heads where a flush finish matters, universal domed heads everywhere else.

Matching the rivet to the repair

• Blind rivets: body panels, mudguards, heat shields, bracket mounting, toolbox and trailer builds, gutters, ducting and cable trays. Use sealed rivets outdoors, and back-up washers behind soft aluminium or plastics.
• Solid rivets: thin aluminium skins, restoration work, any joint that must resist vibration and repeated load, and anywhere you want a flush, period-correct finish.
• Neither: suspension mountings, chassis legs, towbar fixings or seatbelt anchorages. These are structural and should be repaired by the original method — welding or correct high-tensile fasteners — with an eye on insurance and MOT requirements.

Practical tips that save a repair

Clamp or cleco the work before drilling so both sheets are drilled together, then deburr and blow out swarf before setting anything. Isolate dissimilar metals with sealant or a smear of primer to slow galvanic corrosion, and never mix aluminium rivets into stainless structure without thinking about it.

If a blind rivet spins, grip the body with pliers while you work the tool. If a solid rivet refuses to form a clean head, stop, drill it out and start again with the correct length — a badly set rivet is weaker than no rivet at all, and drilling one out later is far more annoying than doing it properly first time.