How Far From the Edge?

Put a rivet too close to the edge of a plate and the load behind it simply rips the metal out to the edge — a failure called tear-out or shear-out. To prevent it, keep the hole center a safe distance back. The usual minimum is about 1.5 to 2 rivet diameters, rising to roughly 2 to 2.5d for aircraft work and countersunk heads.

Edge distance is measured from the center of the hole to the nearest edge of the material. This calculator gives the recommended minimum for your rivet, flags whether the spacing you have is enough, and estimates how much load the strip of metal ahead of the rivet can actually take.

Tear-Out: The Edge Failure Mode

When a rivet pulls toward an edge, the block of material in front of it shears out along two planes running to the edge. The resistance is those two areas times the plate’s shear strength:

where e is the edge distance, d the hole diameter, t the plate thickness and F_v the plate’s ultimate shear strength. More edge distance, a thicker plate or a stronger material all push the capacity up.

Edge Distance, Pitch and the Whole Joint

Edge distance works hand in hand with spacing: pitch controls how the rivets share load along the seam, edge distance protects the ends from tearing out. A joint can have perfect pitch and still fail if the end rivets sit too near the edge. Check both, then confirm rivet shear, bearing and net-section tension as well.